Question

A rectangle has a length of 8.3 cm and a perimeter of 22.4 cm.

Enter the width of the rectangle, in decimal form, in the box.

Answer 1

2.9 cm.

Explanation:

Answer 2

The perimeter is defined as the sum of all the side lengths, and a rectangle has two (possibly different) side lengths - let's call them length and width. There are two lengths, each one is 8.3, so the lengths make 16.6 cm.

We need the two widths, and we have perimeter = 2 lengths + 2 widths. Or 22.4 = 16.6 + 2 widths.

2 widths = 22.4 - 16.6 = 5.8.

1 width is half of 5.8, or 2.9 cm.

Quick check: 22.4 = 8.3 + 8.3 + 2.9 + 2.9