Question 1

3/5 of 4/7 of 7/9 of 425

Accepted Answer

? = 3/5 of 4/7 of 7/9 of 425 ⇒ ? = 3/5 x 4/7 x 7/9 x 425 = 113.33 = 113

Question 2

137% of 12345 =?

Accepted Answer

137% of 12345 = ? ⇒ ? = 12345 x 137/100 = 16912.65 ≈ 17000

Question 3

12.49% of 839.859 =?

Accepted Answer

?= 12.49% of 839.859 ≈ 12% of 840 = 840 x 12/100 = 100.80 ≈ 100

Question 4

121% of 5103 =?

Accepted Answer

? = 5103 x 121/100 = 61.74.63 = 6000

Question 5

124.35 % 8096 =?

Accepted Answer

? = 124.35% of 8096 = (8096 x 124.35)/100 = 1006737.6/100 = 10067.376 = 10000

Question 6

(9.95) 2 x (2.01) 3 = 2 x (?) 2

Accepted Answer

(9.95)2 x (2.01)3 = 2 x (?)2 Here, 9.95 is Approximated to 10, 2.01 is approximate to 2 because calculating the square or cubes of whole number is much easier than to calculate the square or cube of decimal numbers 2 x (?) 2 = ( 10)2 x (2)3 = 100 x 8 = 800 ⇒ (?)2 = 400 ∴ ? =20

Question 7

99.999 ÷ 0.99 ÷ 0.00991234 =?

Accepted Answer

99.999 ÷ 0.99 ÷ 0.00991234 = 100 ÷ 1 ÷ 0.01 = 10000

Question 8

[137 ÷ 17 x 3.99]/[4.02 x 3.98] =?

Accepted Answer

[137 ÷ 17 x 3.99]/[4.02 x 3.98] = ? ≈ (137 ÷ 17 x 4) / (4 x 4) ≈ 2

Question 9

95 3.7 ÷ 95 0.9989 = 95 ?

Accepted Answer

? = 953.7 ÷ 950.9989 = 95? ⇒ 95(3.7 - 0.9989) = 95? ⇒ 952.7011 = 95? ∴ ? = 2.7011 ≈ 2.7

Question 10

3 7.5/27 1.5 x 9 2 = 3 ?

Accepted Answer

3 7.5 ÷ 271.5 x 92 = 3? ⇒ 37.5 ÷ (3)3 x 15 x 32 x 2 = 3 ? ⇒ 37.5 - 4.5 + 4 = 3? ⇒ 37 = 3? ⇒ ? = 7

Question 11

5454 ÷ 54 ÷ 5 =?

Accepted Answer

? = 5454 ÷ 54 ÷ 5 = 5454/(54 x 5) = 5454/270 = 20.2 ≈ 20

Question 12

What approximate value should come in place of the question mark(?) in the following question? ?% of 218 = 3 1/ 3 x 3.3121?

Accepted Answer

?% of 218 = 31/3 x 3.3121 ⇒ 218 x ?/100 = 10/3 x 3.3121 ∴ ? = 10/3 x 3.3121 x 100/218 = 5.064 = 5

Question 13

161% 3578 + 139.85 + 5/8 of 161. 56 =?

Accepted Answer

? = 161% of 3578 + 139.85 + 5/8 of 161.56 = 5760.58 + 139 .85 + 100.975 6001.405 ≈ 6000

Question 14

36.0001 ÷ 5.9998 x √ ? = 108.0005

Accepted Answer

36.0001 ÷ 5.998 x √? = 108.0005 ⇒ 36 ÷ 6 x √? = 108 ⇒ 6 x √? = 108 ∴ √? = 18 ? = 324 ≈ 325

Question 15

1169.997 ÷ 18.001 + 7.0009 x 4.9898 = √ ?

Accepted Answer

1169.9997 ÷ 18.0011 + 7.0009 x 4.9898 = √? ⇒ √? ≈ 1170 ÷ 18 + 7 x 5 = 65 + 35 = 100 ∴ ? = 10000

Question 16

1178.999 x 25.001 - √ ? x 16.0011 = 29075

Accepted Answer

1178.999 x 25.0001 - √? x 16.0011 = 29075 ⇒ 1179 x 25 - √? x 16 = 29075 ⇒ 29475 - √? x 16 = 29075 ⇒ √? x 16 = 29475 - 29075 = 400 ⇒ √? = 25 ∴ ? = 25 x 25 = 625

Question 17

√ 625.04 x 16.96 + 136.001 ÷ 17 =?

Accepted Answer

√625.04 x 16.96 +136.001 ÷ 17 = ? ∴ ? = √625 x 17 + 136 ÷ 17 = 25 x 17 + 136 ÷ 17 = 425 + 8 = 433

Question 18

134% of 3894 + 38.94 % of 134 =?

Accepted Answer

134% of 3894 + 38.94% of 134 = ? ⇒ ? = (3894 x 134)/100 + (38.94 x 134)/100 = 5217.96 + 52.1796 = 5270.1396 ≈ 5270

Question 19

35% of 121 + 85% of 230.25 =?

Accepted Answer

? = 35% of 121 + 85% of 230 .25 = (121 x 135)/100 + (230 x 85)/100 = 4235 + 195.55 = 237.85 ≈ 240

Question 20

22.5% of 1350 + 135% of 225 =?

Accepted Answer

? = 22.5% of 1350 + 135 % of 225 = (1350 x 225)/100 + (225 x 135)/100 = 303.75 + 303.75 = 607.5 ≈ 610

Approximation Questions