Question

The sides of a triangle are in the ratio 3:4:5. What is the length of each side of the perimeter of the triangle is 30 cm?

Answer 1

If the ratio of the sides is 3:4:5, each side will measure respectively 3x,4x and 5x.

Then, we have the following equation to solve this problem:
3x+4x+5x=30

we solve this equation.
3x+4x+5x=30
12x=30
x=30/12
x=2.5

We find out the measure of each side:
3x=3(2.5)=7.5
4x=4(2.5)=10
5x=5(2.5)=12.5

Answer. the length of the sides would be 7.5 cm, 10 cm and 12.5 cm.