The perimeter is 312cm and one side is 11 times smaller than the other. Find sides?

1. Let the smaller side of the rectangle be a, then its larger side is 11a. Add the sides and multiply the sum by 2 to get the perimeter of the rectangle. Let’s solve this equation:

(a + 11a) * 2 = 312,

12a * 2 = 312,

24a = 312,

a = 312/24,

a = 13 cm.

2. Find the large side of the rectangle:

13 cm * 11 = 143 cm.

Answer: the sides of this rectangle are 143 cm and 13 cm.