Approximation Test-3 (Approximation of decimal figures)

Answer: Option C

Explanation

Given,

499.99+1999÷39.99×50.01=?

It can be approximated as

500+2000÷40×50=?

 [ applying BODMAS rule]

= 500+50×50

= 500+2500

= 3000

Hence, Option C is correct.

Answer: Option D

Explanation

Given,

[(7.99)²-(13.001)²+(4.01)³]²=?

It can be approximated as

[(8)²-(13)²+(4)³]²=?

= [64-(169)+64]²

= [128-169]²

= [-41]²

= 1681 ≈ 1660

Hence, Option D is correct.

Answer: Option E

Explanation

Given,

(41.33)²+(7.96)²-(22.02)²=?

It can be approximated as

(42)²+(8)²-(22)²=?

= (1764)+64-484

= 1828-484

= 1344 ≈ 1380

Hence, Option E is correct.

Answer: Option C

Explanation

Given,

(10.998)³=?

It can be rounded off as

(11)³

= 1331 ≈ 1330

Answer: Option B

Explanation

Given,

31.999×12.001×17.5001=?

It can be approximated as

32×12×18=?

= 32×12×20

= 640×12

= 7680 ≈ 6720

Hence, option B is correct.