Explore topic-wise InterviewSolutions in .

This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.

51.

1). 452). 45.73). 47.54). 46

Answer»

For the respective quantity CONSUMED in 1 kg of MIXTURE,

Quantity of type A WHEAT in 1 kg of mixture = (2/5) × 1 = 0.4 kg

Quantity of type B wheat in 1 kg of mixture = 1 – 0.4 = 0.6 kg

For the respective COST price of wheat type,

Cost price for type A = 0.4 × 50 = Rs. 20

Cost price for type B = 0.6 × 30 = Rs. 18

Cost price per kg of mixture = Rs. 38

For the SELLING price,

Selling price – cost price = Profit

⇒ Selling price – 38 = 25% of cost price

⇒ Selling price = (0.25 × 38) + 38

∴ Selling price = Rs. 47.5

52.

1). 1 ∶ 12). 1 ∶ 23). 1 ∶ 34). 1 ∶ 4

Answer»

Let ‘x’ UNITS of both the mixtures be mixed together

TOTAL quantity of NEW mixture = x + x = 2X

Quantity of honey in first mixture = 10% of x = x/10

Quantity of honey in second mixture = 40% of x = 2x/5

⇒ Total quantity of honey in new mixture = x/10 + 2x/5 = x/2

⇒ Quantity of water in new mixture = 2x – x/2 = 3x/2

∴ Ratio of new mixture = x/2 ? 3x/2 = 1 ? 3

53.

How much water must be added to 50 ml of alcohol to make a solution that contains 50% alcohol?1). 5 ml2). 10 ml3). 15 ml4). 50 ml

Answer»

LET the water added be X ML

Total solution = (x+50) ml

% of alcohol = 50%

50/(x + 50) × 100= 50

x = 50 ml
54.

1). 22). 13). 34). 4

Answer»

QUANTITY of water in 300 ml of MIXTURE = [x/(x + 1)] × 300

When 50 ml of water is mixed in the mixture, ratio of acid and water BECOMES 2 ? 5

⇒ Quantity of water in in the new mixture = 5/7 × (300 + 50)

⇒ (x/x + 1) × 300 + 50 = 5/7 × (300 + 50)

⇒ (x/x + 1) × 300 = 200

⇒ (x/x + 1) = 2/3

∴ x = 2

55.

A jar contains a mixture of two liquids A and B in the ratio 3 : 1. When 6 litres of the mixture is taken out and 10 litres of liquid B is poured into the jar, the ratio becomes 1 : 3. How many litres of liquid A was contained in the jar?1). 12.25 litres2). 14.25 litres3). 16.25 litres4). 8.25 litres

Answer»

Let the jar initially contains 3x and x LITRES of mixture A and B respectively

∴ Quantity of A in mixture left = (3x – ¾ × 6) = (3x – 18/4) litres

∴ Quantity of B in mixture left = (x – ¼ × 6) = (x – 6/4) litres

Given,

⇒ (3x – 18/4)/((x – 6/4) + 10) = 1/3

9X – 54/4 = x – 6/4 + 10

⇒ (36x – 54)/4 = (4x – 6 + 40)/4

⇒ 36x – 4x = 34 + 54

32X = 88

⇒ x = 2.75

∴ Amount of liquid A in the jar = 3x = 3 × 2.75 = 8.25 litres
56.

50 litres of alcohol-water mixture of ratio 17 ∶ 8 is mixed with 60 litres of another alcohol-water mixture of ratio 11 ∶ 4. Some more water was added to it to obtain a final mixture of ratio 2 ∶ 1. What is the quantity of final mixture?1). 113 litres2). 117 litres3). 121 litres4). 125 litres

Answer»

Quantity of alcohol in 50 litres of first mixture = 17/25 × 50 = 34 litres

Quantity of water in 50 litres of first mixture = 8/25 × 50 = 16 litres

Similarly,

Quantity of alcohol in 60 litres of second mixture = 11/15 × 60 = 44 litres

Quantity of water in 60 litres of second mixture = 4/15 × 60 = 16 litres

⇒ Total quantity of alcohol in new mixture = 34 + 44 = 78 litres

⇒ Total quantity of water in new mixture = 16 + 16 = 32 litres

Let ‘x’ litres of water be added to obtain the final mixture

⇒ Ratio of final mixture = 78 ? (32 + x) = 2 ? 1

⇒ 78 = 64 + 2x

⇒ x = 14/2 = 7 litres

∴ Total quantity of final mixture = 78 + 32 + 7 = 117 litres
57.

1). 352). 283). 424). 24

Answer»

LET initial quantity of sugar = 4a and milk = 5A

(Initial quantity of sugar)/(Initial quantity of milk + Quantity of milk ADDED) = 2/3

⇒ 4a/(5a + 7) = 2/3

⇒ 10a + 14 = 12a

⇒ 2a = 14

⇒ a = 7 liters

∴ Quantity of Sugar in new MIXTURE is same as initial so = 4a = 4 × 7 = 28 liters

58.

There are 65 students in a class. Among them, Rs 39 is distributed so that each boy gets 80 paise and each girl gets 30 paise. Find the number of boys and girls in that class.1). 40 and 252). 39 and 263). 35 and 304). 45 and 20

Answer»

Average MONEY per student = 3900/65 = 60 paise

Applying the allegation rule:

⇒ (80 - 60)/(60 - 30) = 2/3

BOYS : Girls = 3 : 2

⇒ Number of boys = (65 × 3)/(3 + 2)

⇒ Number of boys = 39

⇒ Number of girls = 65 - 39 = 26

∴ Number of boys is 39 and girls is 26
59.

Two types of sugars are mixed together to make a third type of sugar of Rs. 56 Rs/kg. If the price of 1st and 2nd sugar are 72 Rs/kg and 48 Rs/kg respectively. Find the ratio of 1st and 2nd sugar to be mixed together to make a third type of sugar?1). 2 ∶ 12). 1 ∶ 23). 1 ∶ 34). 3 ∶ 1

Answer»
60.

An alloy has Iron, Silver and Bronze in the ratio 7 : 2 : 3. Another alloy has Silver and Bronze in ratio 1 : 2. In what ratio should the two mixtures be mixed so that the ratio of Iron and Silver in resultant mixture is 5 : 3?1). 2 : 12). 19 : 93). 20 : 114). 21 : 10

Answer»

Suppose M KG of first ALLOY and N kg of second alloy is taken.

Amount of Iron in first alloy = 7M/12 kg

Amount of Silver in first alloy = 2M/12 kg

Amount of Silver in second alloy = N/3 kg

RATIO of Iron and Silver in mixture is 5 : 3.

⇒ (7M/12)/(2M/12 + N/3) = 5/3

⇒ (7M/(2M + 4N)) = 5/3

21M = 10M + 20N

⇒ 11M = 20N

⇒ M/N = 20/11

∴ ratio should be 20 : 11
61.

5 liters of milk is drawn from a tank that has 50 liters of milk. The taken milk is replaced by water and the process is repeated 3 times. The mixture is sold at Rs. 100/L and cost price of milk is Rs. 100/L, then find the profit (In Rs.).1). Rs. 14552). Rs. 13553). Rs. 12554). Rs. 2000

Answer»

MILK left = Capacity X (1 – fraction of milk withdrawn)n, where n is the no of process

⇒ Milk left = 50 × (1 – 5/50)3 = 50 × (45/50)3 = 36.45 L

⇒ Total cost price = 36.45 × 100 = Rs. 3645

⇒ Total selling price = 50 × 100 = Rs. 5000

∴ Required profit = 5000 – 3645 = Rs. 1355
62.

1). 4 : 32). 16 : 273). 4 : 74). 20 : 21

Answer»

Total weight of pulses is 1 kg

Let the weight of RS. 11.10 per kg PRICE be x and Rs. 15.20 per kg PULSE be (1 - x)

Let the ratio in which mixture is mixed be x : (1 - x)

Total price of pulses at Rs. 11.10 per kg = 11.10x

Total price of pulses at Rs. 15.20 per kg = 15.2(1 - x)

Total cost of mixture = (15.2(1 - x) + 11.10x)

(15.2(1 - x) + 11.10x) = 13.20

15.2 - 4.1x = 13.2 ⇒ x = 20/41

Ratio in which mixture is mixed = x : (1 - x) = 20/21 = 20 : 21

63.

By adding 10 liters of water in a mixture of two liquids A and B, the percentage of A in total solution is reduced by 30% and B is 10% of the solution. In this solution, 2 liters of A is added. What is the ratio of water, A and B in the solution respectively? 1). 13 ∶ 15 ∶ 52). 15 ∶ 33 ∶ 53). 12 ∶ 11 ∶ 154). 13 ∶ 33 ∶ 8

Answer»

Let the quantity of A and B in the solution be X and Y.

⇒ After adding 10ltr of water, total solution = X + Y + 10

B is only 10% of the total solution

⇒ Y/ (X + Y + 10) = 0.1----(1)

Initial percentage of A in the solution = (X × 100)/ (X + Y)

New percentage of A in solution = (X × 100)/(X + Y + 10)

This new percentage is 30% less than before

[(X × 100)/(X+Y) - (X × 100)/ (X + Y + 10)]/ [(X × 100)/(X+Y)] = 0.3

 10 /(X+Y+10) = 0.3

X + Y + 10 = 100/3

Putting this in (1) we get

Y = 0.1 × 100/3 = 10/3

X = 70/3 - 10/3 = 20

If 2lts of A is added the amount of A BECOMES 2 + 20 = 22

Ratio of water ? A ? B is = 10 ? 22 ? 10/3 = 15 ? 33 ? 5
64.

In what ratio should tea costing Rs. 300/kg to be mixed with tea costing Rs. 200/kg so that the cost of the mixture is Rs. 225/kg?1). 3 : 12). 1 : 33). 1 : 44). 4 : 1

Answer»

Trick:

⇒ Difference between the prices of TWO tea (a) = 300 - 200 = 100

⇒ Difference between the net price and cheapest (b) = 225 - 200 = 25

REQUIRED ratio = b : (b - a) = 25 : 75 = 1 : 3

Detailed Solution:

Let amount of RS. 300/kg tea added be x and Rs. 200/kg added be 1

⇒ Total cost of tea = 300 × x + 200 × 1 = 200 + 300x

⇒ Amount of tea = 1 + x

⇒ Cost of per kg of mixed tea = Rs 225

⇒ 200 + 300x = 225 × (1 + x)

⇒ x = 1/3

∴ Required ratio = 1 : 3

65.

A drum contains 80 litres of ethanol. 20 litres of this liquid is removed and replaced with water. 20 litres of this mixture is again removed and replaced with water. How much water (in litres) is present in this drum now?1). 452). 403). 354). 44

Answer»

We know the formula:

X = A(1 - R/C)N

Here X = Liquid remaining after replacement

A = Total quantity of liquid before replacement

R = Quantity of replaced liquid

C = Total Capacity of drum

n = No. of times the liquid was replaced

⇒ A = 80, R = 20, C = 80 and n = 2

Putting these VALUES in the formula,

⇒ X = 80 × (1 - 1/4)2

⇒ X = 80 × 9/16

⇒ X = 45 litres

AMOUNT of ethanol present after replacement = 45 litres

∴ Amount of water present after replacement = 80 - 45 = 35 litres
66.

The ratio of spirit and water in the two vessels is 5 : 1 and 3 : 7 respectively. In what ratio the liquid of both the vessels should be mixed such that a new mixture containing half spirit and half water is obtained? 1). 3 : 52). 5 : 73). 1 : 14). 4 : 7

Answer»

3/5 is the CORRECT ANSWER

67.

An alloy contains copper and tin in the ratio 3 : 2. If 250 gm of copper is added to this alloy then the copper in it becomes double the quantity of tin in it. What is the amount (in gm) of tin in the alloy?1). 2502). 7503). 10004). 500

Answer»

? Alloy CONTAINS copper and tin in the ratio 3 : 2

Let the amount of copper in an alloy be 3X

And the amount of tin in an alloy be 2x

According to QUESTIONS,

⇒ 3x + 250 = 2 × 2x

⇒ x = 250 gm

∴ The amount (in gm) of tin in the alloy = 2x = 2 × 250 = 500 gm

68.

A jar contains a blend of juice and water in the ratio of 5 ∶ x. When 1 liter of water is added to 4 liters of the blend the ratio of juice to water becomes 1 ∶ 1. What is the value of x?1). 32). 13). 24). 4

Answer»

Initial ratio = 5 ? x

After ADDING 1 liter of water to the 4 LITERS of blend, the final QUANTITY of the blend BECOMES 5 Liters

Final Ratio = 1 ? 1

⇒ Value of 2 = 5 Liters

⇒ Quantity of juice = Quantity of water in the blend = 2.5 Liters

Since the Quantity of juice is same,

⇒ Quantity of juice in initial mixture = 2.5 Liters

⇒ Quantity of water in initial mixture = 1.5 Liter

⇒ Initial total quantity = 4 Liters

4 Liters in mixed in the ratio = 2.5 ? 1.5 = 5 ? 3

∴ Value of x = 3

69.

10 liters are removed from a cask full of wine containing 60 liters and is then filled with water. 10 liters of mixture is again withdrawn from the container. What quantity of wine is now left in the cask?1). \(41\frac{2}{3}\)2). \(27\frac{3}{6}\)3). 404). 35

Answer»

INITIAL AMOUNT of wine = 60 LITERS.

After replacing 10 liters of wine with water

⇒ There is 50 liters of wine and 10 liters of water.

⇒ Wine to water RATIO = 5: 1

10 liters of this mixture is removed and REPLACED by water.

⇒ Amount of wine removed from the mixture = (5/6) × 10 = 25/3 liters.

Amount of water removed = (1/6) × 10 = 5/3 liters.

Final amount of wine in the mixture = 50 – 25/3 = 125/3 = $(41\frac{2}{3})$ liters.
70.

Two vessels contain milk and water in the ratio of 2 ∶ 3 and 7 ∶ 9. Find the ratio in which the contents of the two vessels have to be mixed so that the ratio of milk and water in the new mixture is equal.1). 5 ∶ 82). 8 ∶ 53). 1 ∶ 24). 2 ∶ 3

Answer»
71.

A and B are two alloys of gold and copper prepared by mixing metals in the ratio 7 ∶ 2 and 7 ∶ 11 resp. If equal quantities of the alloys are melted to form a third alloy C, Find the ratio of gold and copper.1). 6 ∶ 72). 7 ∶ 53). 3 ∶ 84). 7 ∶ 6

Answer»

In 1 KG of alloy A, Gold = 7/9 and Copper = 2/9

In 1 kg of alloy Q, Gold = 7/18 and Copper = 11/18

Ratio of Gold and Copper in alloy C

= 7/9 + 7/18 ? 2/9 + 11/18

= 21 ? 15 = 7 ? 5
72.

1). 61 ∶ 212). 7 ∶ 23). 49 ∶ 154). 51 ∶ 8

Answer»

Initially, in the container amount of milk = 64 litres

Amount of water = 0 litres

First, 8 litres of milk is replaced

∴ Amount of milk = 64 - 8 = 56 litres

Amount of water = 8 litres

RATIO of milk and water = 56 ? 8 = 7 ? 1

Second, 8 litres of MIXTURE is replaced

In this mixture, ratio of milk and water is = 7 ? 1

Thus, amount of milk replaced = $(\frac{7}{8} \times 8 = 7)$ litres

Amount of milk REMAINING = 56 - 7 = 49 litres

Amount of water = 64 - 49 = 15 litres

Now NEW ratio = 49 ? 15

Alternate method :

To find amount of milk

 $({\rm{Original\;amount\;}}{\left( {1 - \;\frac{{Amount\;replaced\;by\;water}}{{Original\;amount}}} \right)^n})$

Where n = number of operations

$(64{\left( {1 - \;\frac{8}{{64}}} \right)^2} = 49)$ litres

Amount of water = 64 - 49 = 15 litres

Now new ratio = 49 ? 15

73.

100 Liters of mixture contains 15% water and rest milk, the amount of milk that must be added so that the resulting mixture contains 87.5% milk is?1). 20 L2). 15 L3). 25 L4). 10 L

Answer»

Amount of water in the MIXTURE = 15L

⇒ Milk = 85 L

On adding the milk to make the concentration of milk 87.5%, the quantity of the milk remains the same,

⇒ 12.5% Water = 15 L

100% = 120 L

⇒ Out of 120 L, concentration of water is 15L

⇒ Quantity of milk = 105 L

∴ Quantity added = 105 – 85 = 20 L
74.

1). Rs. \(61\frac{5}{{19}}\) per kg2). Rs. \(51\frac{7}{{19}}\) per kg3). Rs. \(52\frac{{11}}{{19}}\) per kg4). Rs. \(57\frac{{12}}{{19}}\) per kg

Answer»

TOTAL COST of type 1 wheat = 28 × 56 = Rs. 1,568

Total cost of type 2 wheat = 32 × 80 = Rs. 2,560

Total cost of type 3 wheat = 16 × 33 = Rs. 528

Total cost = 1568 + 2560 + 528 = Rs. 4,656

Total kg = 28 + 32 + 16 = 76kg

∴ Average price = $(\frac{{4656}}{{76}} = Rs.\;61\frac{5}{{19}})$ per kg

75.

How many gallons of each of a 4% and an 11% acid solutions should be mixed to obtain 35 gallons of a 7% solution?1). 20 gallons, 15 gallons2). 22 gallons, 13 gallons3). 13 gallons, 22 gallons4). 15 gallons, 20 gallons

Answer»

Let US denote by y gallons the AMOUNT of 4% solution.

⇒ The amount of solution of 11% acid solution = 35 - y gallons

 

Amount of solution (gallons)

Percentage

Amount of SOLVENT (gallons)

Component 1

y

0.04

0.04y

Component 2

35 - y

0.11

0.11 (35 - y)

Mixture

35

0.07

0.07 (35) = 0.04y + 0.11 (35 - y)

 

SOLVING 0.07 (35) = 0.04y + 0.11 (35 - y),we get

y = 20 gallons

If y = 20 gallons; then the other amount, denoted by 35 - y must be 35 - 20 = 15 gallons.
76.

1). 122). 163). 154). 18

Answer»

Let the number of RED and blue BALLS in the box be 5x and 3x respectively.

Given that 16 balls are removed from the box and replaced with 16 other blue balls

⇒ Number of red balls in the box left after this PROCESS = 5x – (5/8 × 16)

⇒ 5x – 10

⇒ Number of blue balls in the box left after this process = 3x – (3/8 × 16)

⇒ 3x – 6

Since 16 additional balls were added to the box,

⇒ Total number of blue balls in the box will be (3x – 6 + 16)

⇒ 3x + 10

Given that the ratio of number of red and blue balls after this process = 3/5

⇒ (5x – 10)/(3x + 10) = 3/5

⇒ (5x – 10) × 5 = (3x + 10) × 3

⇒ 25x – 50 = 9x + 30

⇒ 16x = 80

⇒ x = 5

INITIAL number of blue balls PRESENT in the box initially = 3 × 5 = 15

77.

1). 160 ml2). 120 ml3). 280 ml4). None of these

Answer»

⇒ Let ‘x’ be the quantity of milk in the original mixture

⇒ $(\frac{7}{3} = \frac{x}{{120}})$

⇒ Quantity of milk, x = (120 × 7)/3 = 280ml

⇒ the mixture contains 280 ml of milk and 120 ml of water

⇒ The expected new RATIO of milk : water is 1 : 1

⇒ Let ‘y’ be the EXTRA water added to make the mixture have milk and water in equal parts

THUS, 120 + y = 280

⇒ y = 160 ml

∴ Extra water added = 160 ml

78.

1). 48 litres2). 60 litres3). 66 litres4). 90 litres

Answer»

MILK ? Water ? Sugar syrup = 9 ? 4 ? 1

Amount = 84 litres

Amount of milk = $(\FRAC{9}{{14}} \TIMES 84 = 54)$ litres

Amount of water = $(\frac{4}{{14}} \times 84 = 24)$ litres

Amount of sugar syrup = $(\frac{1}{{14}} \times 84 = 6)$ litres

Let x be amount of water added and y be amount of sugar syrup, such that RATIO of mixture becomes 9 ? 6 ? 2.

54 ? (24 + x) ? (6 + y) = 9 ? 6 ? 2

Now, 54 ? (24 + x) = 9 ? 6

∴ (54)(6) = (24 + x)(9)

∴ x = 12 litres

Also, 54 ? (6 + y) = 9 ? 2

∴ (54)(2) = (6 + y)(9)

∴ y = 6 litres

Amount of water = 24 + 12 = 36

Amount of sugar syrup = 6 + 6 = 12 litres

Amount of milk and sugar syrup = 54 + 12 = 66 litres

79.

A lotion of 7 ml contains 50% alcohol. How much quantity of water should be added to the lotion to make it 20% alcoholic lotion?1). 7 ml2). 10 ml3). 9 ml4). 10.5 ml

Answer»

Given, LOTION of 7 ml contains 50% alcohol.

∴ Amount of water = 50% of 7ml = 3.5ml

Amount of alcohol = 50% of 7ml = 3.5 ml

Let the water added be ‘a’ ml.

Now, in order to obtain 20% alcohol SOLUTION.

$(\frac{{3.5}}{{7 + a}} \times 100\%= 20\% \;)$

⇒ 5 × 3.5 = 7 + a

⇒ a = 10.5 ml

80.

A dishonest milkman buys milk at Rs. 20 per litre and adds 1/3 of water to it and sells the mixture at Rs. 24 per litre. What is his gain?1). 25 percent 2). 60 percent3). 37.5 percent4). 66.67 percent

Answer»

Let the milkman buy X litre of milk at 20 per ltr

⇒ Cost Price = 20x

ADDS 1/3 of water to it so quantity = x + (x/3) = 4x/3

⇒ Selling Price = 24 × (4x/3) = (96x/3)

⇒ Gain % = (SP - CP) × (100/CP)

⇒ Gain % = {(96x/3) - 20x} × (100/20x)

⇒ Gain % = (3600x)/60x

∴ Gain % = 60%
81.

1). Rs. 39 per kg2). Rs. 40 per kg3). Rs. 44 per kg4). Rs. 45 per kg

Answer»

Total price of type 1 rice = 450 × 96 = RS. 43,200

Total price of type 2 rice = 550 × x = Rs. 550x

Total kg = 450 + 550 = 1000kg

Average price = Rs. 66.3

Total price of the mixture = 66.30 × 1000 = Rs. 66,300

Price of type 2 rice per kg = x = $(\frac{{66300\; - \;43200}}{{550}})$ = Rs. 42 per kg

82.

Three bottles of equal capacity have mixture of milk and water in ratio 5 : 7, 7 : 9 and 2 : 1 respectively. These three bottles are emptied into a large bottle. What is the percentage of milk in the new mixture?1). 49.62). 52.33). 51.24). 50.7

Answer»

Let the capacity of each bottle be y

For bottle 1, milk be 5A and water be 7a

⇒ 5a + 7a = y

⇒ a = y/12…(i)

For bottle 2, milk be 7b and water be 9b

⇒ 7b + 9b = y

⇒ b = y/16…(ii)

For bottle 3, milk be 2C and water be c

⇒ 2c + c = y

⇒ c = y/3…(iii)

PERCENTAGE of milk can be given as = (5a + 7b + 2c) × 100/(5a + 7b + 2c + 7a + 9b + c)

⇒ Percentage of milk = (5a + 7b + 2c) × 100/(12a + 16b + 3c) …from (i), (ii) and (iii)

⇒ Percentage of milk = (5 × y/12 + 7 × y/16 + 2 × y/3) × 100/(y + y + y)

⇒ Percentage of milk = 50.7%

∴ the percentage of milk be 50.7%

83.

A mixture contains Pepsi and water in ratio 5 : 2. It contains 15 litres more Pepsi than water. If 5 litres of water is added to the mixture. Find the new ratio of Pepsi and water in the mixture?1). 4 : 52). 5 : 33). 3 : 54). 5 : 4

Answer»

DIFFERENCE of Pepsi and WATER = 5 unit - 2 unit = 3 UNITS

⇒ 3 units = 15 litres

⇒ 1 unit = 5 litres

Quantity of Pepsi = 5 units = 5 × 5 = 25 litres

Quantity of water = 2 units = 2 × 5 = 10 litres

Now 5 litres of water is added to the mixture

New Quantity of water = 10 + 5 = 15 litres

New ratio of Pepsi and water = 25 : 15

∴ Pepsi : water = 5 : 3
84.

The ratio of milk and water in three samples is 1 ∶ 3, 3 ∶ 5 and 11 ∶ 5. A mixture containing equal quantities of all three samples is made. What will be the ratio of milk and water in the new mixture?1). 7 ∶ 92). 5 ∶ 73). 15 ∶ 134). 9 ∶ 11

Answer»

Let ‘X’ quantity of each of three MIXTURES to be mixed

Quantity of milk in the new MIXTURE = (1/4)x + (3/8)x + (11/16)x = 21x/16

Quantity of water in the new mixture = (3/4)x + (5/8)x + (5/16)x = 27x/16

REQUIRED RATIO = (21x/16) ? (27x/16) = 7 ? 9
85.

A solution has 15% sugar. Another solution has 5% sugar. How many liters of the second solution must be added to 20 liters of the first solution to make a solution of 13% sugar?1). 4 liters2). 5 liters3). 3 liters4). 2 liters

Answer»

Let y liters of the second SOLUTION must be added.

Then, [15 × 20 + 5 × y]/(20 + y) = 13

On SOLVING, we GET y = 5 litres
86.

1). 1102). 553). 2204). 70

Answer»

Let the mixture is of ‘13x’ litres

⇒ Quantity of milk in the mixture = 11x litres

⇒ Quantity of WATER in the mixture = 2x litres

After adding 35 litres of water, new mixture has (2x + 35) part water

After adding 35 Litres of water, the new mixture will contain twice as much pure milk as water.

⇒ 11x/ (2x + 35) = 2/1

⇒ 4x + 70 = 11x

⇒ 11x - 4x = 70

7X = 70

⇒ x = 10 litres

∴ Quantity of milk in the mixture = 11x = 110 litres
87.

1). 49 L2). 51 L3). 48 L4). 39 L

Answer»

According to QUESTION,

x(50/100) + 3x(40/100) + 8X(60/100) = 26

⇒ 0.5x + 1.2x + 4.8x = 26

⇒ x = 26/6.5 = 4 L

The total volume of SOLUTION A and B = x + 3x + 8x = 12x = 12 × 4 = 48 L

∴ The total volume of solution A and B = 48 L

88.

Two equal vessels are filled with the mixtures of water and milk in the ratio of 3 : 4 and 2 : 3 respectively. If the mixtures are poured into a third vessel, the ratio of water and milk in the third vessel will be1). 15 : 412). 53 : 353). 29 : 414). 59 : 53

Answer»

⇒ Let the quantity of milk and water in 1st and 2nd vessel be 3x, 4x and 2X, 3x respectively.

⇒ Milk in the first mixture = 3x/(3x + 4x) = 3/7

⇒ Water in the first mixture = 4x/(3x + 4x) = 4/7

⇒ Milk in the SECOND mixture = 2x/(2x + 3x) = 2/5

⇒ Water in the second mixture = 3x/(2x + 3x) = 3/5

⇒ Ratio of Milk and water in new mixture = (3/7 + 2/5)/(4/7 + 3/5)

⇒ Ratio of Milk and water in new mixture = {(3 × 5 + 2 × 7)/35}/{(4 × 5 + 3 × 7)/35} 

⇒ Ratio of Milk and water in new mixture = (15 + 14)/(20 + 21)

∴ Ratio of Milk and water in new mixture = 29 : 41
89.

1). 148 kg2). 150 kg3). 171 kg4). 192 kg

Answer»
90.

An 80 litre mixture of water and acid contains 20% acid. How much acid should be added to make the acid 60% in the new mixture?1). 602). 803). 704). 90

Answer»

LET the quantity of new mixture is ‘a’ litres

ACID in the mixture = 20% of 80 LITRE = 16 litres

Water in the mixture = 80 – 16 = 64 litres = 80% of the mixture

In new mixture water is only 40% and acid is 60%

Water in new mixture = 40% of a litres = 64 litres

⇒ 2/5 × a = 64 litres

⇒ a = 160 litres

Acid in new mixture = 160 – 64 = 96 litres = 60% of the new mixture

∴ Acid that should be added = 96 – 16 = 80 litres
91.

1). 18 litres2). 24 litres3). 32 litres4). 40 litres

Answer»

LET the QUANTITY of the wine in the CASK originally be x litres

Then, quantity of wine left in cask after 4 OPERATIONS = {x (1 – 8/x)?} litres

⇒ {X (1 – 8/x)?}/x = 16/81

⇒ (1 – 8/x)? = (2/3)?

⇒ (X – 8)/x = 2/3

⇒ 3x – 24 = 2x

∴ x = 24 litres

92.

1). 37.5 hours2). 34.5 ​hours3). 38 ​hours4). 40 ​hours

Answer»

TOTAL salt present in 1 kg of 5% solution = 5 × 1000/100 = 50gm.

Saturation LIMIT of salt is 200gm per Litre.

AMOUNT of WATER required to dissolve 50gm of salts = 50 × 1000/200 = 250ml.

Rate of evaporation = 20gm/ hour.

∴ Amount to be evaporated for sedimenting = 1000 - 250 = 750GM.

Time taken to evaporate 750gm = 750/20 = 37.5 hours.

∴ After 37.5 Hours sedimentation will start.
93.

Ramsukh sells rasgulla at Rs. 15 per kg. A rasgulla is made up of flour and sugar mixed in the ratio 5 : 3. The ratio of price of sugar and flour is 7 : 3. He earns \(66\frac{2}{3}\%\) profit. What is the cost price of sugar?1). Rs. 10/kg2). Rs. 9/kg3). Rs. 18/kg4). Rs. 14/kg

Answer»

Given, he earns a profit of $(66\frac{2}{3}\% .)$ LET C be the COST price per kg of the rasgulla.

$(\Rightarrow 66\frac{2}{3} = \frac{{15 - C}}{C} \times 100)$ 

2C = 45 – 3C

⇒ C = 9

Let the cost price of one kg of sugar be 7x and that of one kg of flour be 3x. Since they are MIXED in the ratio 3 : 5, we have:

$(9 = \frac{3}{8}\left( {7x} \RIGHT) + \frac{5}{8}\left( {3x} \right) = \frac{{36x}}{8})$ 

⇒ x = 2

Hence, price of sugar is Rs.14 /kg
94.

A vessel is filled with liquid, 3 parts of which are water and 5 parts syrup. How much of the mixture must be drawn off and replaced with water so that the mixture will be half water and half syrup?1). \(\frac{1}{3}\)2). \(\frac{1}{4}\)3). \(\frac{1}{5}\)4). \(\frac{1}{7}\)

Answer»

LET the Initial quantity of LIQUID be 8 litres

∴ After replacing ‘x’ litres with water,

Water in mixture = 3 - 3x/8 + x = 3 + 5x/8

Syrup in mixture = 5 - 5x/8

According to the given CONDITION,

⇒ 3 + 5x/8 = 5 - 5x/8

∴ 5x/4 = 2

∴ x = 8/5

∴ For 8 litres, 8/5 of the mixtures must be TAKEN off

∴ For 1 litre, 8/5 × 1/8 = 1/5 part must be replaced
95.

A 450 ml mixture of two liquids contains 30% liquid A and the rest is liquid B. How much liquid B must be added so that the mixture contains 80% liquid B?1). 150 ml2). 225 ml3). 240 ml4). 330 ml

Answer»

Quantity of liquid B = 70% of 450 = 315 ML

Let x ml of liquid B be added.

315 + x = 80% of (450 + x)

⇒ 315 + x = 0.8 × (450 + x)

⇒ 315 + x = 360 + 0.8x

⇒ 0.2x = 45

⇒ x = 225
96.

In what ratio should 20% ethanol solution be mixed with 40% ethanol solution to obtain a 28% ethanol solution?1). 2 ∶ 32). 8 ∶ 53). 3 ∶ 24). 5 ∶ 8

Answer»

Let the ratio of 20% ethanol to 40% ethanol be X ? 1,

According to the QUESTION,

⇒ x × 0.2 + 1 × 0.4 = (x + 1) × 0.28

⇒ 0.08x = 0.12

⇒ x = 3/2

REQUIRED Ratio = 3 ? 2
97.

One test tube contains some chemical and another test tube contains an equal quantity of water. To prepare a solution, 20 g of the chemical is poured into the second test tube. Then, two-thirds of the formed solution is poured from the second test tube into the first. If the fluid in the first test tube is four times that in second, what quantity of water was taken initially.1). 150 g2). 120 g3). 90 g4). 40 g

Answer»

LET y g of WATER and chemical was taken.

Initially 1st process

First test TUBE = (y – 20) g

Second test tube = (y + 20) g

2nd process

First test tube = (y – 20) + (y + 20) × (2/3)

Second test tube = (y + 20) × (1/3)

Now,

(y -20) + (2/3)(y +20) = 4 × (1/3)(y + 20)

On solving, y= 40 g
98.

1). Rs. 252). Rs. 30 3). Rs. 32 4). Rs. 35

Answer»

The Pomegranate ADDED = (¼) of glass

Price of Pomegranate juice = (1/4) × 40 = RS. 10

CARROTS added = (¼) of glass

Price of carrots juice = (1/4) × 40 = Rs. 10

Orange added = ½ of glass

Price of orange juice = (1/2) × 30 = Rs. 15

Price of MIXTURE juice = 10 + 10 + 15 = Rs. 35 

99.

1). 96 litres2). 84 litres3). 68 litres4). 74 litres

Answer»

Juice ? MILK ? Water = 2 ? 9 ? 7

Amount = 108 litres

Amount of juice = $(\frac{2}{{18}} \times 108 = 12)$ litres

Amount of milk = $(\frac{9}{{18}} \times 108 = 54)$ litres

Amount of water = $(\frac{7}{{18}}\; \times 108 = 42)$ litres

Let x be amount of milk added and y be amount of water, such that ratio of mixture BECOMES 1 ? 7 ? 6

12 ? (54 + x) ? (42 + y) = 1 ? 7 ? 6

Now, 12 ? (54 + x) = 1 ? 7

∴ (12)(7) = 54 + x

∴ x = 30 litres

Also, 12 ? (42 + y) = 1 ? 6

∴ (12)(6) = 42 + y

∴ y = 30 litres

Amount of water = 42 + 30 = 72 litres

Amount of juice and water = 12 + 72 = 84 litres

100.

A mixture contains milk and water in the ratio of 5 : 3. When some more milk is added to it, the ratio of milk to water in the resulting mixture becomes 2 : 1. If the initial Quantity of mixture was 800 liters, then find the quantity of the final mixture (in liters).1). 860 liters2). 900 liters3). 1000 liters4). 1050 liters

Answer»

LET the quantity of additional milk is x liters

In the mixture of 800 liters

Quantity of milk = (5/8) × 800 = 500 liters

So the quantity of water is = 300 liters

According to the QUESTION,

⇒ (500 + x)/300 = 2/1

⇒ 500 + x = 600

⇒ x = 600 – 500 = 100 liters

So, the new quantity of the mixture is 800 + 100 = 900 liters

∴ The final quantity of the mixture is 900 liters