A certain sum lent out at simple interest amounts to Rs 575 in 3 yr and to Rs 625 in 5 yr. Then the rate of interest is?

Let the sum be Rs 'y' and , rate of interest = R%
Simple Interest for 2 yr =Rs( 625 - 575 ) = Rs 50
∴ Sum of money, y=Rs( 575 - 75)= Rs 500
∴ R= [(100 x SI)/(Sum x Time)]
=[(100x 75)/(500 x 3)]=5 %