Question

If a sum becomes 28/25 of itself in 5 years then find the rate of interest ?​

Answer 1

Answer:

140/125.

Step-by-step explanation:

28x5=140

25x5=125

Answer 2

Given: Time, T=5 years

Let the principal be P

Rate of interest= R

Amount, A=8P5

Simple Interest, S.I= Amount − Principal=

8P5−P

=3P5

∴S.I=3P5

Again, S.I=P×R×T100

⇒3P5=P×R×5100

⇒35=5R100

R=3×205

R=3×4

∴R=12.

The required rate of interest is

12%.