Question

A student is trying to find the area of a rectangle. He records the length as 10 cm while the width is 16.6 cm.

What is the area of the rectangle? (Use the formula: Length × Width). Select the answer with the correct number of
significant figures.
A) 26.6 cm²
B) 166 cm²
C) 200 cm²
D) 170 cm²

Answer 1

The area of the rectangle is 166 cm²; however, when rounded to two significant figures, the correct answer is 170 cm², which corresponds to option D.

Step-by-step explanation:

To calculate the area of a rectangle, you multiply the length by the width. In this case, the length is 10 cm, and the width is 16.6 cm. Hence, the area is calculated as follows:

Area = Length × Width = 10 cm × 16.6 cm = 166 cm²

As for significant figures, since the width (16.6 cm) is reported to three significant figures, and the length (10 cm) is reported to two significant figures, the result should be expressed in two significant figures because the number with the fewest significant figures in the calculation determines the number of significant figures in the answer. Therefore, the area, rounded to two significant figures, is 170 cm².

Answer D is correct.