Question

The difference between the compound
interest
and
the
simple
interest
on
₹ 42000
for
two years is ₹ 105 at the same rate of interest per annum. Find

(i) the rate of interest
(ii) the compound interest earned in second year.​

Answer 1

P = Rs 42000 T=2 years

Let rate = r %

S.I=100PRT=10042000×r×2=840 Rs

For C.I

A=P(1+100r)n

=42000(1+100r)2

=42000(1+10000r2+50r)

=42000+1042r2+840r

C.I = A - P

=42000+1042r2+840r−42000

=1042r2+840r

Given C.I−S.I=105

=1042r2+840r−840r=105

=1042