A rectangular sports field has dimensions 150 m by 120 m. Its length is increased by 0.8 percent and its width is reduced by 0.5 percent. What is the approximate percent change in the area of the field?

AAbout 0.3% ✓ Correct

BAbout 0.4%

CAbout 1.3%

DAbout 1.6%

Correct answer: (A) About 0.3%

Explanation

The area changes by about 0.3%.

Percent area change = +0.8 - 0.5 + (0.8 x -0.5)/100.

The product term is about -0.004%, negligible.

So the change is about 0.8 - 0.5 = 0.3%.

The area rises by roughly 0.3%.

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