Question

Which does NOT show a reasonable estimate of 360 * 439?

A 100,000
B 140,000
C 160,000
D 180,000

Answer 1

A. 100000 is your answer

Answer 2

A. 100,000

Explanation:

Given expression,

`360* 439`

Since, when we round only 439,

∵ 439 ≈ 400 ( nearest hundred )

`360* 439\approx 360* 400 = 144000\approx 140,000`

Hence, option 'B' shows a reasonable estimation,

When we round both 439 and 360 to nearest hundred,

That is, 439 ≈ 400, 360 ≈ 400

`360* 439\approx 400* 400 = 160,000`

Hence, option 'C' shows a reasonable estimation,

When we round 360 to nearest hundred and 440 to nearest ten,

That is, 360 ≈ 400, 439 ≈ 440

`360* 439\approx 400* 440= 175600\approx 180,000`

Hence, option 'D' shows a reasonable estimation.