One side of the rectangle is 30 cm, and the other is 3 times smaller. Find the area of the rectangle.

We are given a rectangle with sides: 30 cm, and the other is 3 times smaller. Let’s find the second side:
1) 30: 3 = 10 cm – the length of the second side.
You need to calculate the perimeter. To do this, we will use the formula:
P = a + a + b + b; where a, b are the sides of the rectangle.
There is a shortened formula:
P = (a + b) * 2; where a, b are the sides of the rectangle.
Using the formula, we find the perimeter:
P = (a + b) * 2 = (30 + 10) * 2 = 80 cm perimeter of the rectangle.
You need to calculate the area. To do this, we will use the formula:
S = a * b; where a, b are the sides of the rectangle.
S = a * b = 30 * 10 = 300 cm² – the area of ​​the rectangle.
Answer: Perimeter – 80 cm, area – 300 cm².