The perimeter of a rectangular painting is 320 cm. If the length of the painting is 99 cm, what is its width?
Let's denote the width of the painting as w.
The formula for the perimeter of a rectangle is given by P = 2l + 2w, where l is the length and w is the width.
Given that the length of the painting is 99 cm and the perimeter is 320 cm, we can set up the equation:
320 = 2(99) + 2w
320 = 198 + 2w
2w = 320 - 198
2w = 122
Dividing by 2 on both sides, we get:
w = 61
Therefore, the width of the rectangular painting is 61 cm.