260 + Interview Questions in Maths in Class 8 Page 4 InterviewSolution

151.	Complete the magic square
Answer» ANSWER :`(##RSA_MAT_VIII_C05_E03_014_A01##)`

Discussion

152.	Using the formula (a+b)^(2) = (a^(2) + 2ab+b ^(2)), evaluate: (310)^(2) (508)^(2) (630)^(2) (196)^(2) (689)^(2)
Answer» ANSWER :585832

Discussion

153.	If three equal chords meet at three distinct points on the circle, then the angle between any two chords is ____________.
Answer» ANSWER :`60^(@)`

Discussion

154.	A and B are two non-empty sets so n(A) +1 = n(B). The difference of the cardinalnumber of their power sets is 448. Find the number of elements of B.
Answer» 9 8 7 6 Solution :(i) `2^(n(A)) - 2^(n(B)) = 448` and PROCEEDS. (II) `2^(n(A)) - 2n^(n(B)) = 448`,where `n(A)` and `n(B)` are INTEGERS.

Discussion

155.	Find the volume and the total surface area of a cuboid ,whose:l = 3.5 m, b = 2.6 m and h = 90 cm .
Answer» ANSWER :` 8.19 m ^(3); 29 18 m ^(2) `

Discussion

156.	Each side of a rhombus is 18 cm. If thedistance between two parallel sides is 12 cm,find its area.
Answer» ANSWER :`216 CM^(2)`

Discussion

157.	Replace A,B and C by suitable numerals.({:(," "AB),(,""xxBA):})/(" "(B+1)CB)
Answer» ANSWER :A=1, B=3, C=0

Discussion

158.	Find the area of an equilateral triangle, whose one side is a cm.
Answer» Answer :`(sqrt(3))/(4)a^(2)CM^(2)`

Discussion

159.	Find the area of of a triangle, whose sidesare : 21 m, 28 m and 35 m
Answer» ANSWER :`294 m^(2)`

Discussion

160.	If the weight of 9 sheets of thick paper is 30 grams, how many sheets of the same paper would weigh 1(1)/(4) kilograms?s
Answer» ANSWER :375

Discussion

161.	Find the sum of exterior angles obtained on producing, in order, the sides of a polygon with: (i) 7 sides (ii) 10 sides (iii) 250 sides
Answer» ANSWER :`(i) 360^@ (II) 360^@ (III) 360^@`

Discussion

162.	Fill in the blanks with the correct symbol out of gt, = and lt : {:((i)(-3)/(7)....... (6)/(-13),(ii) (5)/(-13).....(-35)/(91),(iii) -2.......(-13)/(5)),((iv) (-2)/(3)........ (5)/(-8),(v) 0........(-3)/(-5),(vi) (-8)/(9) ......... (-9)/(10)):}
Answer» Answer :`(i) GT (II) = (iii) gt (IV) lt (V) lt (vi) gt`

Discussion

163.	The ratiobetweenthe lengths of the edges of two cubesare in the ratio3: 2Find theratiobetween their : total surface area (ii)volume.
Answer» ANSWER :32 m

Discussion

164.	The total surface area of cubeis216 cm ^(2)Find its volume.
Answer» ANSWER :` 216 CM ^(3) `

Discussion

165.	A certain sum of money, invested for 5 years at 8% p.a. simple interest, earns an interest of Rs. 12,000. Find : (i) the sum of money. (ii) the compound interest earned by this money in two years at 10% p.a. compound interest.
Answer» ANSWER :(i) RS. 30,000(II) Rs. 6,300

Discussion

166.	AB, BC and CD are three consecutive sides of a regular polygon. If the angle BAC=20^@, find (i) its each interior angle (ii) its each exterior angle (iii) the number of sides in the polygon.
Answer» Answer :`(i) 140^@ (II) 40^@ (iii) 9 `

Discussion

167.	A circle is passing through three vertices of a rhombus of side 8 cm and its centre is the fourth gest diagonal of the rhombus ( in cm).
Answer» `8sqrt(3)` `4sqrt(3)` `6 SQRT(3)` `2sqrt(3)` ANSWER :a

Discussion

168.	Find the volume, curved surface area and total surface area of each of the cylinders whose dimensions are: (i) radius of the base =7cm and height =50 cm (ii) radius of the base =5.6 m and height =1.25 m (iii) radius of the base k=14 dm and height =15 m
Answer» Answer :(i) `7700 CM^(3), 2200 cm^(2), 2508 cm^(2)` (II) `123.2 m^(2), 44 m^(2),241.12 m^(2)` (iii) `92.4 m^(3), 132 m^(2), 144.32 m^(2)`

Discussion

169.	Two angles of a hexagon are 120^@ and 160^@. If the remaining four angles are equal, find each equal angle.
Answer» `190^@` `140^@` `110^@` `120^@` ANSWER :C

Discussion

170.	Find the area of of a triangle, whose sidesare : 10 cm, 24 cm and 26 cm
Answer» ANSWER :`120CM^(2)`

Discussion

171.	A and B can do a piece of work in 15 days, C and A in 20 days . How many days will be taken by A, B and C working togther to finish the work?
Answer» ANSWER :10 DAYS

Discussion

172.	Arrange the following rational numbers in descending order: (i)-2, (-13)/(6), (8)/(-3), (1)/(3)(ii) (-3)/(10), (7)/(-15), (-11)/(20), (17)/(-30) (iii) (-5)/(6), (-7)/(2), (-13)/(18), (23)/(-24) (iv) (-10)/(11), (-19)/(11), (-23)/(33), (-39)/(44)
Answer» Answer :(i) ` (1)/(3) gt -2 gt (-13)/(6) gt (8)/(-3) ` (ii) `(-3)/(10) gt (7)/(-15) gt (-11)/(20) gt (17)/(-30) ` (III) `(-7)/(12) gt (-13)/(18) gt (-5)/(6) gt (23)/(-24) ` (iv) `(-23)/(33) gt (-19)/(22) gt (-39)/(44) gt (-10)/(11) `

Discussion

173.	A thin metal iron-sheet is a rhombus in shape,with each side 10 m. If one of its diaginals is 16 m, find the cost of painting its both sides at the rate ofRs. 6 per m^(2).Also, find the distance between the oppositesides of this rhombus.
Answer» ANSWER :RS. 1,152; 9.6 m

Discussion

174.	A cuboid is 8 m long . 12 m broad and 3.5 m high. Find its lateralsurface area.
Answer» ANSWER :` 140 m ^(2) `

Discussion

175.	The perimeter of a trapezium is 52 cm and its non-parallel sides are 9 cm and 11 cm respectively. If its height is 8 cm. find the area of traplezium.
Answer» ANSWER :`128 CM^(2)`

Discussion

176.	A path of uniform width, 2.5 m, runs aroundthe inside of a rectangular field 30 m by 27 m.Find the area of the path.
Answer» ANSWER :`260 m^(2)`

Discussion

177.	45 % of the students of a class participated in Physics Olympaid and 65 % of the students of the class participated in Maths Olympiad. 4 students participated in neither of these two and 8 students participated in both. (i) Find how many students are there in the class ? (ii) Participated only in maths Olympiad ? (iii) Participated in at least one Olympiad ?
Answer» ANSWER :(i) 40 , (II) 18 , (III) 36

Discussion

178.	Use the information given in the adjoining figure to find : (i) the length of AC. (ii) the are a of DeltaABC. (iii) the length of BD,correct to one decimal place.
Answer» ANSWER :(i) 25 CM (II) `84 cm^(20`(iii) 6.7 cm

Discussion

179.	A solid cuboid metal has dimensions 24cm .18 cm and 4cmFind the volume.
Answer» ANSWER :` 1728 CM ^(3)`

Discussion

180.	In a building, there are 24 cyclinderpillars, For eachpillar , radiusis 28 cm andheightis4m . Find the total cost to paintingthe curvedsurfacearea of the pillarsat the rate of8 " per "m^(2)
Answer» ANSWER :RUPES 1,35, 168

Discussion

181.	The ratio between the interior angle and the exterior angle of a regular polygon is 2: 1. Find : (i) each exterior angle of the polygon. (ii) number of sides in the polygon.
Answer» ANSWER :`(i) 160^@ (II) 6`

Discussion

182.	One angle of a seven-sided polygon is 114^@ and each of the other six angles is x^@. Find the magnitude of x^@.
Answer» `144^@` `131^@` `122^@` `191^@` ANSWER :B

Discussion

183.	A parallelogram has sides of 20 cm and 30 cm.If the distance between its shorter sides is15 cm, find the distance between the longer sides.
Answer» ANSWER :10 CM

Discussion

184.	Plot the points A(2, 4) and B(4, 2) on a graph sheet and draw a line passing through these two points. Extend the line on both sides to meet the coordinate axes. What are the coordinates of the points where this line meets the x-axis and the y-axis?
Answer» ANSWER :(6, 0) and (0, 6)

Discussion

185.	Find the value of each of the using the column method: (23)^(2) (35)^(2) (52)^(2) (96)^(2) (67)^(2) (86)^(2) (137)^(2) (256)^(2)
Answer» ANSWER :65536

Discussion

186.	Three solid cubesof edges6 cm , 10 cmand x cmare meltedto forma singlecube of edge12 cm.Find the value of x.
Answer» ANSWER :X= 8

Discussion

187.	Find the square root of the number by using the method of prime factorisation: 225 441 729 1296 2025 4096 7056 8100 9216 11025 15876 17424
Answer» ANSWER :15

Discussion

188.	The radius of a circular wheel is 42 cm. Findthe distance travelled by it in: (i) 1 revolution (ii) 50 revolutions (iii) 200 revolutions
Answer» ANSWER :(i) 2.64 m (II) 132 m (III) 528 m

Discussion

189.	For each inequation , given below, represent the solution on a number line: -2(x+8) le 8, x in R
Answer» ANSWER :`{X GE -12, x in R}` `(##SEL_RKB_ICSE_MAT_VIII_C15_E02_018_A01##)`

Discussion

190.	At what rate per cent of simple interest will the interest on Rs. 3,750 be one-fifth of itself in 4 years? To what will it amount in 15 years ?
Answer» ANSWER :`5%` and RS. Rs. 6,562.50

Discussion

191.	P,Q and R started a piece of work. They worked on it for 5 days, whichP left
Answer» <P> SOLUTION :(a) (p+q+r) worked for 5 days, (Q+R) worked for 5 days and R worked for 5 days to complete the work. (b) P worked for 5 days, Q worked for 10 days and R worked for 15 days to complete the work.(iii) Find the part of the work done by Q and R. (C ) Then find the part of the work done by P. (d) Compare them. When certain people work for the same number of days each, then the ratio of the total work done will be the same as the work done by each of them per day. Hence, if all the people involved work for the same number of days, then the earning can directly be distributed in the ratio of work done per day by each of them . The following example is useful to understand this statement.

Discussion

192.	The two parallel sides and the distancebetween them are in the ratio 3: 4: 2. If thearea of the trapezium is 175 cm^(2),find its height.
Answer» ANSWER :10 CM

Discussion

193.	The perimeter of a square is 28 cm. Find its: (i) one side (ii) area (iii) diagonal
Answer» ANSWER :(i) 7 CM (ii) `49CM^(2)` (iii) 9.898 cm

Discussion

194.	Find the radius and area of a circle, whosecircumference is :22 m
Answer» ANSWER :3.5 m and 38.5 `m^(2)`

Discussion

195.	Find the radius and area of a circle, whosecircumference is :6.16 m^(2)
Answer» ANSWER :1.4 m and 8.8 m

Discussion

196.	Angles of a quadrilateral are (4x)^@, 5(x+2)^@, (7x-20)^@ and 6(x+3)^@. Find: (i) the value of x. (ii) each angle of the quadrilateral.
Answer» Answer :`(i) x=16^@ (II) 64^@, 90^@, 92^@ and 114^@`

Discussion

197.	Is it possible to have a regular polygon whose each exterior angle is : (i) 80^@ (ii) 40% of a right angle
Answer» ANSWER :(i) No (II) YES

Discussion

198.	Three cubes , each of edge 8 cm , are joined as shown alongside . Find the totalsurface area and the volume of the cuboid.
Answer» ANSWER :` 1536 CM ^(3) `

Discussion

199.	Locate the points A(1, 2), B(3, 4) and C(5, 2) on a graph sheet taking suitable axes. Write the coordinates of the fourth point D in order to complete the rhombus ABCD. Measure the diagonals of this rhombus and check whether they are equal or not.
Answer» ANSWER :D(3, 0); No

Discussion

200.	The perimeter of a rectangle is 46 m and itslength is 15 m. Find its : (i) breadth (ii) area (iii) diagonal
Answer» Answer :(i) 8M (II) `120m^(2)` (iii) 7 m

Discussion

Explore topic-wise InterviewSolutions in .

Complete the magic square

Using the formula (a+b)^(2) = (a^(2) + 2ab+b ^(2)), evaluate: (310)^(2) (508)^(2) (630)^(2) (196)^(2) (689)^(2)

If three equal chords meet at three distinct points on the circle, then the angle between any two chords is ____________.

A and B are two non-empty sets so n(A) +1 = n(B). The difference of the cardinalnumber of their power sets is 448. Find the number of elements of B.

Find the volume and the total surface area of a cuboid ,whose:l = 3.5 m, b = 2.6 m and h = 90 cm .

Each side of a rhombus is 18 cm. If thedistance between two parallel sides is 12 cm,find its area.

Replace A,B and C by suitable numerals.({:(," "AB),(,""xxBA):})/(" "(B+1)CB)

Find the area of an equilateral triangle, whose one side is a cm.

Find the area of of a triangle, whose sidesare : 21 m, 28 m and 35 m

If the weight of 9 sheets of thick paper is 30 grams, how many sheets of the same paper would weigh 1(1)/(4) kilograms?s

Find the sum of exterior angles obtained on producing, in order, the sides of a polygon with: (i) 7 sides (ii) 10 sides (iii) 250 sides

Fill in the blanks with the correct symbol out of gt, = and lt : {:((i)(-3)/(7)....... (6)/(-13),(ii) (5)/(-13).....(-35)/(91),(iii) -2.......(-13)/(5)),((iv) (-2)/(3)........ (5)/(-8),(v) 0........(-3)/(-5),(vi) (-8)/(9) ......... (-9)/(10)):}

The ratiobetweenthe lengths of the edges of two cubesare in the ratio3: 2Find theratiobetween their : total surface area (ii)volume.

The total surface area of cubeis216 cm ^(2)Find its volume.

A certain sum of money, invested for 5 years at 8% p.a. simple interest, earns an interest of Rs. 12,000. Find : (i) the sum of money. (ii) the compound interest earned by this money in two years at 10% p.a. compound interest.

AB, BC and CD are three consecutive sides of a regular polygon. If the angle BAC=20^@, find (i) its each interior angle (ii) its each exterior angle (iii) the number of sides in the polygon.

A circle is passing through three vertices of a rhombus of side 8 cm and its centre is the fourth gest diagonal of the rhombus ( in cm).

Find the volume, curved surface area and total surface area of each of the cylinders whose dimensions are: (i) radius of the base =7cm and height =50 cm (ii) radius of the base =5.6 m and height =1.25 m (iii) radius of the base k=14 dm and height =15 m

Two angles of a hexagon are 120^@ and 160^@. If the remaining four angles are equal, find each equal angle.

Find the area of of a triangle, whose sidesare : 10 cm, 24 cm and 26 cm

A and B can do a piece of work in 15 days, C and A in 20 days . How many days will be taken by A, B and C working togther to finish the work?

Arrange the following rational numbers in descending order: (i)-2, (-13)/(6), (8)/(-3), (1)/(3)(ii) (-3)/(10), (7)/(-15), (-11)/(20), (17)/(-30) (iii) (-5)/(6), (-7)/(2), (-13)/(18), (23)/(-24) (iv) (-10)/(11), (-19)/(11), (-23)/(33), (-39)/(44)

A thin metal iron-sheet is a rhombus in shape,with each side 10 m. If one of its diaginals is 16 m, find the cost of painting its both sides at the rate ofRs. 6 per m^(2).Also, find the distance between the oppositesides of this rhombus.

A cuboid is 8 m long . 12 m broad and 3.5 m high. Find its lateralsurface area.

The perimeter of a trapezium is 52 cm and its non-parallel sides are 9 cm and 11 cm respectively. If its height is 8 cm. find the area of traplezium.

A path of uniform width, 2.5 m, runs aroundthe inside of a rectangular field 30 m by 27 m.Find the area of the path.

Use the information given in the adjoining figure to find : (i) the length of AC. (ii) the are a of DeltaABC. (iii) the length of BD,correct to one decimal place.

A solid cuboid metal has dimensions 24cm .18 cm and 4cmFind the volume.

In a building, there are 24 cyclinderpillars, For eachpillar , radiusis 28 cm andheightis4m . Find the total cost to paintingthe curvedsurfacearea of the pillarsat the rate of8 " per "m^(2)

The ratio between the interior angle and the exterior angle of a regular polygon is 2: 1. Find : (i) each exterior angle of the polygon. (ii) number of sides in the polygon.

One angle of a seven-sided polygon is 114^@ and each of the other six angles is x^@. Find the magnitude of x^@.

A parallelogram has sides of 20 cm and 30 cm.If the distance between its shorter sides is15 cm, find the distance between the longer sides.

Plot the points A(2, 4) and B(4, 2) on a graph sheet and draw a line passing through these two points. Extend the line on both sides to meet the coordinate axes. What are the coordinates of the points where this line meets the x-axis and the y-axis?

Find the value of each of the using the column method: (23)^(2) (35)^(2) (52)^(2) (96)^(2) (67)^(2) (86)^(2) (137)^(2) (256)^(2)

Three solid cubesof edges6 cm , 10 cmand x cmare meltedto forma singlecube of edge12 cm.Find the value of x.

Find the square root of the number by using the method of prime factorisation: 225 441 729 1296 2025 4096 7056 8100 9216 11025 15876 17424

The radius of a circular wheel is 42 cm. Findthe distance travelled by it in: (i) 1 revolution (ii) 50 revolutions (iii) 200 revolutions

For each inequation , given below, represent the solution on a number line: -2(x+8) le 8, x in R

At what rate per cent of simple interest will the interest on Rs. 3,750 be one-fifth of itself in 4 years? To what will it amount in 15 years ?

P,Q and R started a piece of work. They worked on it for 5 days, whichP left

The two parallel sides and the distancebetween them are in the ratio 3: 4: 2. If thearea of the trapezium is 175 cm^(2),find its height.

The perimeter of a square is 28 cm. Find its: (i) one side (ii) area (iii) diagonal

Find the radius and area of a circle, whosecircumference is :22 m

Find the radius and area of a circle, whosecircumference is :6.16 m^(2)

Angles of a quadrilateral are (4x)^@, 5(x+2)^@, (7x-20)^@ and 6(x+3)^@. Find: (i) the value of x. (ii) each angle of the quadrilateral.

Is it possible to have a regular polygon whose each exterior angle is : (i) 80^@ (ii) 40% of a right angle

Three cubes , each of edge 8 cm , are joined as shown alongside . Find the totalsurface area and the volume of the cuboid.

Locate the points A(1, 2), B(3, 4) and C(5, 2) on a graph sheet taking suitable axes. Write the coordinates of the fourth point D in order to complete the rhombus ABCD. Measure the diagonals of this rhombus and check whether they are equal or not.

The perimeter of a rectangle is 46 m and itslength is 15 m. Find its : (i) breadth (ii) area (iii) diagonal