The perimeter of the rectangle is 60cm, its length is 20cm. find the width of the rectangle.

The perimeter of the rectangle is 60 centimeters.
The length of the rectangle is 20 centimeters.
The width of the rectangle is?
To solve the problem, we need a formula for calculating the perimeter of a rectangle: P = (a + b) * 2, where, a and b are the values of the length and width of the rectangle. Now we substitute the known values according to the condition of the problem and solve the equation:
60 = (20 + b) * 2.
60 = 40 + 2b.
60-40 = 2b.
20 = 2b.
b = 20: 2.
b = 10. centimeters.
To check, we substitute it into the formula and solve it:
Verification:
1) (20 + 10) * 2 = 30 * 2 = 60, the solution is correct.
Answer: the width of the rectangle is 10 centimeters.