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⇒ 35.2 × 420/24 + 533.9 - 210.9 = X% of 8500

⇒ 616 + 533.9 - 210.9 = X% of 8500

⇒ 1149.9 - 210.9 = X% of 8500

⇒ 939 = 85X

⇒ 939/85 = X

FOLLOW BODMAS RULES to solve the equation

Step-1: The part of the equation containing 'Brackets' must be solved first, and in the bracket,

Step-2: Any mathematical 'Of' or 'Exponent' must be solved NEXT,

Step-3: Next, the parts of the equation that contain 'Division' and 'Multiplication' are solved

Step-4: At last, the part of the equation that contains 'Addition' and 'Subtraction' should be solved.

⇒ 725.34 + 887.12 – (2 × ?) = 999.88

⇒ 725.34 + 887.12 – 999.88 = 2 × ?

⇒ 1612.46 – 999.88 = 2 × ?

⇒ 612.58 = 2 × ?

∴ ? = 306.29

$(\sqrt {\sqrt {44944} + \sqrt {52441} } = ?\; + \;6)$

$(\sqrt {212 + 229} = \;?\; + \;6)$

$(?\; + \;6 = \sqrt {441})$

⇒ ? = 21 - 6

⇒ ? = 15

$(? = \SQRT[5]{{{{\LEFT( {243} \right)}^2}}})$

⇒ ? = (243)^(2⁄5)

⇒ ? = (3 × 3 × 3 × 3 × 3)^(2⁄5)

⇒ ? = (3⁵)^(2⁄5)

⇒ ? = 3²

Follow these BODMAS rules to solve the question

Step-1? The part of the EQUATION containing 'Brackets' must be solved first, and in the BRACKET,

Step-2? Any MATHEMATICAL 'Of' or 'Exponent' must be solved next,

Step-3? Next, the parts of the equation that contain 'Division' and 'Multiplication' are solved

Step-4? At last, the part of the equation that contains 'Addition' and 'Subtraction' should be solved.

960 ÷ 2.4 × 3.5 + 275 = 25 × ?

$( \Rightarrow {\rm{\;}}\frac{{960}}{{24}} \times 10 \times \frac{7}{2}\; + \;275\; = \;25 \times \;?)$

⇒ 400 × 7/2 + 275 = 25 × ?

⇒ 1400 + 275 = 25 × ?

⇒ 1675 = 25 × ?

⇒ ? = 1675/25

⇒ ? = 67

400.06² + 24.99 – 30.009³ + 2.001⁵

⇒ 400² + 25 +2⁵ – 30³

⇒ 160000 + 25 + 32 – 27000

⇒ 160057 – 27000

⇒ 133057

The given expression:

81% of 2310 – 34% of 1596 =?

$(= \LEFT( {\frac{{81}}{{100}} \times 2310} \right) - \left( {\frac{{34}}{{100}} \times 1596} \right))$

= (81 × 23.10) - (34 × 15.96)

= 1871.1 – 542.64

= 1328.46

Follow these BODMAS rules to solve the question

Step-1? The part of the EQUATION containing 'Brackets' must be SOLVED first, and in the BRACKET,

Step-2? Any MATHEMATICAL 'Of' or 'Exponent' must be solved next,

Step-3? Next, the parts of the equation that contain 'Division' and 'Multiplication' are solved

Step-4? At last, the part of the equation that contains 'Addition' and 'Subtraction' should be solved.

⇒ 135.79 + 142.81 + 172.91 + 2 × ? = 750.97

⇒ 2 × ? = 750.97 – (135.79 + 142.81 + 172.91)

⇒ 2 × ? = 750.97 – (451.51)

⇒ 2 × ? = 299.46

Follow BODMAS rule to SOLVE this question, as per the order given below,

Step-1-Parts of an equation ENCLOSED in 'Brackets' MUST be solved first,

Step-2-Any MATHEMATICAL 'Of' or 'Exponent' must be solved next,

Step-3-Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step-4-Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

The given expression:

{4 × [√324 + √1296]}^1/3

= {4 × [√324 + √1296]}^1/3

= {4 × [18 + 36]}^1/3

= { 4 × 54}^1/3

= (216)^1/3

Follow BODMAS rule to solve this question, as per the ORDER given below,

Step-1: Parts of an equation enclosed in 'Brackets' must be SOLVED first,

Step-2: Any mathematical 'Of' or 'Exponent' must be solved NEXT,

Step-3: Next, the parts of the equation that contain 'Division' and 'Multiplication' are CALCULATED,

Step-4: Last but not LEAST, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Now, the given expression,

15083 + 25% of ? + 289 = 16385.5

⇒25% of ? = 1013.5

Follow BODMAS rule to SOLVE this question, as per the order given below,

Step-1- Parts of an equation enclosed in ‘Brackets’ must be SOLVED first,

Step-2- Any mathematical ‘Of’ or ‘Exponent’ must be solved next,

Step-3- Next, the parts of the equation that contain ‘Division’ and ‘Multiplication’ are calculated,

Step-4- Last but not the least, the parts of the equation that contain ‘Addition’ and ‘SUBTRACTION’ should be calculated.

Now, the given expression is,

⇒ 223 + (12 × 146) ÷ (87 ÷ 29)

⇒ 223 + 1752 ÷ 3

⇒ 223 + 584

24.98% of 119.98 – 74.93% of 60.07 = ?

Take approximate values

⇒ 24.98 ≈ 25

⇒ 119.98 ≈ 120

⇒ 74.93 ≈ 75

⇒ 60.07 ≈ 60

Putting APPROXIMATED values in the equation

⇒ (25/100) × 120 – (75/100) × 60 = ?

⇒ 30 – 45 = -15

FOLLOW BODMAS rule to solve this question, as per the order given below,

Step-1: Parts of an equation ENCLOSED in 'Brackets' MUST be solved first, and in the BRACKET,

Step-2: Any mathematical 'Of' or 'Exponent' must be solved next,

Step-3: Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step-4: Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Given expression is,

[(75.81 – 12) ÷ 16] = (?)²

Approximating to the CLOSEST integers

⇒ [(76 – 12) ÷ 16] = ?²

⇒ [64 ÷ 16] = ?²

⇒ x² = 4

GIVEN expression is,

⇒ 199.99 - 99.89 ÷ 24.80 = 28.04 × ?

We can write the given values as:

⇒ 199.99 ≈ 200 and 99.89 ≈ 100

⇒ 24.80 ≈ 25 and 28.04 ≈ 28

⇒ 200 - 100 ÷ 25 = 28 × ?

⇒ 200 - 4 = 28 × ?

⇒ 196 = 28 × ?

⇒ ? = 196/28

⇒ 15949.80/X + 43.7% of 1400 - 363.9 = 17.2% of 9500

⇒ 15949.80/X + 611.8 - 363.9 = 1634

⇒ 15949.80/X + 247.9 = 1634

⇒ 15949.80/X = 1634 - 247.9

⇒ 15949.80/X = 1386.1

⇒ 15949.80/1386.1 = X

Follow BODMAS rule to solve this question, as per the ORDER given below,

Step-1- Parts of an equation enclosed in 'Brackets' MUST be solved first, and in the bracket,

Step-2- Any mathematical 'Of' or 'Exponent' must be solved next,

Step-3- Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step-4- Last but not the LEAST, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Given EXPRESSION,

50.44 × 3.19 – 37.15 % of 300 = 24.26 + ?

We can also write values as:

50.44 ≈ 50, 3.19 ≈ 3, 37.15 ≈ 37, 24.26 ≈ 24

Given expression becomes,

⇒ 50 × 3 – 37 % of 300 = 24 + ?

⇒ 150 – 37/100 × 300 = 24 + ?

⇒ 150 – 111 = 24 + ?

⇒ 39 = 24 + ?

Follow BODMAS RULE to solve this QUESTION, as per the order given below,

Step-1- Parts of an equation enclosed in 'Brackets' must be solved first, and in the bracket, the BODMAS rule must be followed,

Step-2- Any MATHEMATICAL 'Of' or 'Exponent' must be solved next,

Step-3-Next, the parts of the equation that contain 'Division' and 'Multiplication' are CALCULATED,

Step-4-Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

3463 × 295 – 16511 = ? + 7983

⇒ 1021585 – 16511 = ? + 7983

GIVEN expression:

60% of 20% of (3/5)th of (?)=450

⇒ (60/100) × (20/100) × (3/5) × ? = 450

⇒ (3/5) × (1/5) × (3/5) × ? =450

⇒ ? = 450 × (125/9)

⇒ ? = 50 × 125

⇒ ? = 6250

The given expression,

780.059 + 49.937 × 30.079 – 59.591 = ?

We can WRITE the given values as,

780.059 ≈ 780, 49.937 ≈ 50, 30.079 ≈ 30 and 59.591 ≈ 60

Then,

⇒ 780 + 50 × 30 – 60 = ?

⇒ ? = 780 + 1500 – 60

⇒ ? = 2280 – 60

$(\FRAC{{? + 2.8 + 5.6}}{{3.5 - 2.1}} = 15)$

⇒? $({? + 8.4\over 1.4})$ = 15

⇒ ? = 15 × 1.4 - 8.4 = 12.6

GIVEN Expression is:

(8)³ ÷ (16)² × 32 = (2)^?-3 ÷ (2)²

$(\begin{array}{l} \Rightarrow \frac{{{{({2^3})}^3}}}{{{{({2^4})}^2}}} \times {2^5} = \frac{{{2^{? - 3}}}}{{{2^2}}}\\ \Rightarrow \frac{{{2^9}}}{{{2^8}}} \times {2^5} = {2^{? - 5\;}} \end{array})$

⇒ 2⁶ = 2^{? – 5}

Comparing powers from both the sides

⇒ 6 = ? – 5

The given expression MAY be SIMPLIFIED as:

$(\Rightarrow 4\frac{{16}}{{17}} \times 1\frac{{11}}{{16}} \div \frac{{21}}{{38}} = \frac{{84}}{{17}} \times \frac{{27}}{{16}} \times \frac{{38}}{{21}})$

$(= \frac{{86184}}{{5712}})$

$(= \frac{{513}}{{34}})$

$(= 15\frac{3}{{34}})$

FOLLOW BODMAS RULE to solve this question, as per the order GIVEN below,

Step-1-Parts of an EQUATION enclosed in 'Brackets' must be solved first,

Step-2-Any MATHEMATICAL 'Of' or 'Exponent' must be solved next,

Step-3-Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step-4-Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

 Now, the given expression,

1002 ÷ 50 × 99 – 1299 =?

⇒ ? = 1002 ÷ 50 × 99 – 1299

⇒ ? = 20.04 × 99 – 1299

⇒ ? = 1983.96 – 1299

⇒ ? = 684.96

Hence, the required answer is 684.96.

Follow BODMAS RULE to solve this question, as per the order given below,

Step-1- Parts of an EQUATION ENCLOSED in 'Brackets' must be solved first, and in the bracket,

Step-2- Any mathematical 'Of' or 'Exponent' must be solved next,

Step-3- Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step-4- Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Given expression is,

⇒ 115.72 ÷ 4.10 × 4.90 = 90.14% of 200 - ?

We can write the given values as :

⇒ 115.72 ≈ 116 and 4.10 ≈ 4

⇒ 4.90 ≈ 5 and 90.14 ≈ 90

Then,

⇒ 116 ÷ 4 × 5 = 90% of 200 - ?

⇒ 116 ÷ 4 × 5 = (90/100) × 200 - ?

⇒ 29 × 5 = 90 × 2 - ?

⇒ 145 = 180 - ?

⇒ ? = 180 - 145

Solve the given question, using FOLLOWING laws of indices,

Laws of Indices,

1-: a^m × aⁿ = a^{{m + n}}

2-: a^m ÷ aⁿ = a^{{m - n}}

3-: [(a^m)ⁿ] = a^mn

4-: (a)^1/m = $(\SQRT[m]{a})$

5-: (a)^-m = 1/a^m

6-: (a)^(m/n) = $(\sqrt[n]{{{a^m}}})$

7-: a⁰ = 1

⇒ 1 - {1 + (a² -1)^-1}^-1

$(\begin{array}{l} \Rightarrow 1 - {\left\{ {1 + \frac{1}{{{a^{2\;}} - 1}}} \right\}^{ - 1}}\\ \Rightarrow 1 - {\left\{ {\frac{{{a^2}}}{{{a^2} - 1}}} \right\}^{ - 1}}\\ \Rightarrow 1 - \left\{ {\frac{{{a^2}}}{{{a^2} - 1}}} \right\}^{ - 1}\\ \Rightarrow \frac{1}{{{a^2}}} \END{array})$

Solution: The given EQUATION is:

(64 ÷ 4) 32 - √296 + 34 × 2 ÷ 2

By APPLYING BODMAS rule,

(In BODMAS rule, B stands for Brackets, O stands for Orders or pOwers, D stands for Division, M stands for Multiplication, A stands for Addition, S stands for Subtraction. For simplification, when we USE BODMAS rule, firstly OPEN the bracket, then resolve ORDER, after then division, multiplication, addition and then subtraction.)

= 16 × 32 - √296 + 34 × 2 ÷ 2

 = 16 × 32 - √296 + 34 × 1

= 512 – 17.20 +34

Follow BODMAS RULE to solve this QUESTION, as per the order GIVEN below,

Step-1-Parts of an EQUATION enclosed in 'Brackets' must be solved first,

Step-2-Any mathematical 'Of' or 'Exponent' must be solved next,

Step-3-Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step-4-Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Now, the given expression,

28 × 104 ÷ (28 – 21 + 6) + 3 = ?

⇒ ? = 28 × 104 ÷ 13 + 3

⇒ ? = 28 × 8 + 3

Follow BODMAS rule to SOLVE this question, as per the ORDER given below,

Step-1- PARTS of an equation enclosed in 'Brackets' must be solved first, and in the bracket,

Step-2- Any mathematical 'Of' or 'Exponent' must be solved next,

Step-3- Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step-4- LAST but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Given expression is,

121 ÷ (7/5 × 3/8 × 4/5) = ?

⇒ ? = 121 ÷ (21/50)

⇒ ? = 121 × 50/21

⇒ ? = 6050/21

This QUESTION, though EASY, could end up giving wrong ANSWERS due to haste

The best policy to answer such questions is to group TOGETHER the terms with equivalent decimal point

⇒ (12.21 + 12.12 + 21.12 + 21.21) + 121.2 + 1.121

⇒ 66.66 + 121.2 + 1.121

⇒ 187.86 + 1.121 = 188.981

In this type of question, we are expected to calculate APPROXIMATE value (not exact value), so we can replace the GIVEN numbers by their nearest perfect places which makes the CALCULATION easy.

We can WRITE the given values as:

731 ≈ 730

12.5 ≈ 13

Now, given expression:

73570 ÷ 731 × 12.5

≈ 73570 ÷ 730 × 12.5

≈ 1259.8

$(\FRAC{5}{{27 - ?}} - \frac{1}{4} = \frac{3}{8})$

⇒? $(\frac{3}{{8}} + \frac{1}{4} = \frac{5}{27\: -\:?})$

⇒? ?$(\frac{5}{{27 - ?}} = \frac{5}{8})$

⇒? 27 - ? = 8

⇒? ? = 27 - 8 = 19

Given expression is,

(59.10 × 4.93) + 15.34 = 49.88 × 3.17 + 32.08 × ?

We can write the given VALUES as:

59.10 ≈ 59 and 4.93 ≈ 5 and 15.34 ≈ 15

49.88 ≈ 50 and 3.17 ≈ 3 and 32.08 ≈ 32

Then,

⇒ (59 × 5) + 15 = 50 × 3 + 32 × ?

⇒ 295 + 15 = 50 × 3 + 32× ?

⇒ 295 + 15 = 150 + 32 × ?

⇒ 310 = 150 + 32 × ?

⇒ 310 - 150 = 32 × ?

⇒ 160 = 32 × ?

FOLLOW BODMAS rule to solve this question, as per the order given below,

Step -1: Parts of an equation enclosed in the ‘BRACKETS’ must be solved first

Step - 2: Any mathematical ‘OF’ or ‘EXPONENTS’ must be solved next

Step - 3: Next the part of the equation that contains ‘DIVISION; and ‘MULTIPLICATION’ are calculated

Step - 4: Last but not least, the parts of the equation that contains ‘ADDITION’ and ‘SUBTRACTION’ should be calculated

Now, the given EXPRESSION:

⇒ 205 × 13 × ? = 16812.5 + 12502.5

⇒ 2665 × ? = 29315

Given expression:

⇒ 48% of 250 + 1050 ÷ 3 – √(?) = 423

⇒ (48/100) × 250 + 1050 ÷ 3 – √(?) = 423

⇒ (48/100) × 250 + 350 – √(?) = 423

⇒ 120 + 350 – √(?) = 423

⇒ 470 – √(?) = 423

⇒ √(?) = 470 – 423

⇒ √(?) = 47

Given EXPRESSION is,

⇒ 69.709 - 32.94 × 1.98 = 149.86 ÷ ?

We can WRITE the given VALUES as 

⇒ 69.709 ≈ 70 and 32.94 ≈ 33

⇒ 1.98 ≈ 2 and 149.86 ≈ 150

⇒ 70 - 33 × 2 = 150 ÷ ?

⇒ 70 - 66 = 150 ÷ ?

⇒ 4 = 150 ÷ ?

⇒ ? = 150/4

$(\begin{ARRAY}{l} \RIGHTARROW \sqrt[3]{{\left( {340 + \SURD 9} \right)}}\\ \Rightarrow \sqrt[3]{{\left( {340 + 3} \right)}}\\ \Rightarrow \sqrt[3]{{343}}\\\THEREFORE \sqrt[3]{{\left( {343 + \sqrt 9 } \right)}} = 7\end{array})$

9 + 54 = ? - 120

63 + 120 = ?

? = 183

Follow BODMAS rule to solve this question, as per the order given below,

Step - 1 - PARTS of an equation enclosed in 'Brackets' must be SOLVED first, and in the bracket,

Step - 2 - Any mathematical 'Of' or 'Exponent' must be solved next,

Step - 3 - Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step - 4 - Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Given expression is,

⇒ 49.99% of 800 + 35.001% of 99.99 = ?

Approximating to the closest integers

⇒ 50% of 800 + 35% of 100

⇒ 400 + 35

81^1/2 = 3^{4 × ½} = 3²

3² × 3⁴ = 3⁶

3⁶ = 27^?

3⁶ = 3^{3 × ?}

6 = 3 × ?

? = 2

Given expression:

$(4\frac{1}{2} + \left( {1 \div 2\frac{8}{9}} \right) - 3\frac{1}{{13}} = ?)$

$(\Rightarrow \;? = \frac{9}{2} + \left( {\frac{1}{{\frac{{26}}{9}}}} \right) - \frac{{40}}{{13}})$

$(\Rightarrow \;? = \frac{9}{2} + \frac{9}{{26}} - \frac{{40}}{{13}})$

$(\Rightarrow \frac{{117 + 9 - 80}}{{26}} = \frac{{46}}{{26}} = \;\frac{{23}}{{13}} = 1\frac{{10}}{{13}})$

HENCE, the required ANSWER is $(1\frac{{10}}{{13}})$

By using BODMAS RULE,

Solving the Brackets,

8.893 ≈ 9

(9 × 9) = 81

Solving Addition,

143.9687 ≈ 144

897.4534 ≈ 897

144 + 897 + 81 = 1122

Given EXPRESSION is,

69.90 ÷ 2.15 + 35.20 = 59.79 ÷ ? + 39.91

We can WRITE the given VALUES as:

69.90 ≈ 70 and 2.15 ≈ 2

35.20 ≈ 35 and 59.79 ≈ 60 and 39.91 ≈ 40

Then,

⇒ 70 ÷ 2 + 35 = 60 ÷ ? + 40

⇒ 35 + 35 = 60 ÷ ? + 40

⇒ 70 = 60 ÷ ? + 40

⇒ 70 - 40 = 60 ÷ ?

⇒ 30 = 60 ÷ ?

⇒ ? = 60/30

⇒ 660 × X + 495.85 - 60% of 9650 = 37.5% of 7200

⇒ 660X + 495.85 - 5790 = 2700

⇒ 660X + 495.85 = 2700 + 5790

⇒ 660X = 8490 - 495.85

⇒ X = 7994.15/660

$(\begin{array}{l} 3\FRAC{1}{{13}} - 4\frac{1}{2} - \left( {1 \div 2\frac{8}{9}} \right) + 1\frac{9}{{25}}\\ = \frac{{40}}{{13}} - \frac{9}{2} - \left( {1 \div \frac{{26}}{9}} \right) + \frac{{34}}{{25}}\\ = \frac{{40}}{{13}} - \frac{9}{2} - \left( {1 \times \frac{9}{{26}}} \right) + \frac{{34}}{{25}}\\ = \frac{{40}}{{13}} - \frac{9}{2} - \frac{9}{{26}} + \frac{{34}}{{25}}\\ = \frac{{40 \times 50 - 9 \times 325 - 9 \times 25 + 34 \times 26}}{{650}}\\ = \frac{{2000 - 2925 - 225 + 884}}{{650}}\\ = \frac{{2884 - 3150}}{{650}}\\ = - \frac{{266}}{{650}} = - \frac{{133}}{{325}} \end{array})$

Follow BODMAS rule to solve this question, as per the order given below,

Step -1- Parts of an EQUATION enclosed in 'Brackets' must be solved FIRST, and in the bracket,

Step -2- Any MATHEMATICAL 'Of' or 'Exponent' must be solved next,

Step -3- Next, the parts of the equation that contain 'Division' and 'Multiplication' are calculated,

Step -4- Last but not least, the parts of the equation that contain 'Addition' and 'Subtraction' should be calculated.

Given expression is,

? – 7/18 = 17/10 – ?

⇒ ? + ? = 17/10 + 7/18

⇒ 2 × ? = [(17 × 9) + (7 × 5)]/ 90

⇒ 2 × ? = (153 + 35) /90

⇒ 2 × ? = 188/90

According to the BODMAS rule, the PRIORITY in which the OPERATIONS should be done is:

⇒ 54.92% of 601 + 66% of 889.979 × 34.905 = (?)

Approximating the value to the nearest integer:

⇒ 55% × 600 + 66% × 890 × 35 = (?)

⇒ 55/100 × 600 + 66/100 × 890 × 35 = (?)

(?) = 330 + 20559

(?) = 20889

$(18\FRAC{2}{3} - 7\frac{1}{4} = ? + 1\frac{1}{2})$

$(\frac{{56}}{3} - \frac{{29}}{4} = ? + \frac{3}{2})$

$(\frac{{224 - 87}}{{12}} = ? + \frac{3}{2})$

$(\frac{{137}}{{12}} = ? + \frac{3}{2})$

$(? = \frac{{119}}{{12}})$

(80.0003% of 1601.73) + (75.123% of 1003.158) + 1000 - (50.82% of 3005.72) × 2.0007

Using BODMAS rule,

⇒ (80% of 1600) + (75% of 1000) + 1000 - (50% of 3000) × 2,

⇒ (80 × 16) + (75 × 10) + 1000 - (50 × 30) × 2, (SIMPLIFYING ‘brackets’)

⇒ 1280 + 750 + 1000 - 1500 × 2,

⇒ 3030 - 3000,

⇒ 30

Let the MAXIMUM MARKS in the EXAMINATION are ‘x’.

Now, according to the question,

Minimum required marks = 35% of the total marks = 0.35x

And, the student gets 200 marks and fails by 10 marks, it means he gets 10 marks less than PASSING marks.

⇒ 200 = 0.35x – 10

⇒ 210 = 0.35x

⇒ x = 210/0.35 = 600.

Given expression is,

⇒ (27.92% of 600) + (? × 1.99) = (8 × 15.79) + (31.94 × 4.11)

$(\Rightarrow \frac{{28}}{{100}} \times 600 + \left( {? \times 1.99} \right) = \left( {8 \times 15.79} \right) + \left( {31.94 \times 4.11} \right))$

⇒ 28 × 6 + (? × 2) = (8 × 16) + (32 × 4)

⇒ 168 + (? × 2) = 128 + 128

⇒ 168 + (? × 2) = 256

⇒ ? × 2 = 88

⇒ ? = 88/2 = 44

⇒ ? = 44