Question

Perimeter of a rectangle is 30 and it's ratio is 3:7 what is it's sides

Answer 1

Ratio = 3 : 7

Define x:

Let x be the constant ratio

Ratio = 3x : 7x

Solve x:

2(3x + 7x) = 30

2(10x) = 30

20x = 30

x =3/2

Find the sides:

3x = 3(3/2) = 19/2 = 4.5 cm

7x = 7(3/2) = 21/2 = 10.5 cm

Answer: The sides are 4.5 cm and 10.5 cm

Answer 2

let the sides 3x and 7x
perimeter of rectangle = 30
2( l + b ) = 30
by putting value
2 ( 3x + 7x ) = 30
2( 10x ) = 30
10x = 30/2
10x = 15
x = 15/10
x = 1.5
3x = 3×1.5 = 4.5
7x = 7×1.5 = 10.5