Question

the ratio of amount for 3years and 2years for fixed rate of interest on a fixed amount is 21:20 . then rate of interest is​

Answer 1

Let the principal be P and rate be R

first Interest=(P*R*3)/100

second Interest=(P*R*2)/100

Given that the ratio of first interest to second interest is 21:20

So, (3PR/100)/(2PR/100)=21:20

3PR/2PR=21/20

The P is same in both interest so P will be cancelled.

3 R1/2 R2 = 21/20

R1/R2=(21*2)/(20*3)

R1:R2 = 7:10

Rate of Interest for 1st year=7%

Rate of Interest for 2nd year = 10%