Question

The perimeter of a rectangular photo frame is 90 cm. The length is twice the width. What are the length and width of the frame? (Hint: The formula for perimeter is where w is the width, l is the length, and P is the perimeter.)

Answer 1

The formula for perimeter of a rectangle is
2(w + l) = P
Since the length of the frame is twice its width,
2(w + 2w) = 90cm. Thus, 2(3w) = 90cm
6w = 90cm
Therefore, w = 90/6.
w = 15