Answer:
=225/16cm^2
Step-by-step explanation: 
Given 
The ratio of the length to the width of the rectangle =3:2.
The perimeter of a rectangle = 60cm.
Solution 
Let length=3x
width=2x
Perimeter of rectangle=2(length + width)
2(3x+2x)=60
5x*2=60
10X=60
X=60/10
X=6
SO LENGTH =3×6=18cm
WIDTH=2×6
 =12cm
 Let perimeter of the square=5x
Length of rectangle=6x
 6x = 18
 X=18/6
 X=3
SO PERIMETER OF SQUARE=5×3
 4SIDE=15
 Side=15/4
Area of square=15/4×15/4
 =225/16cm^2