Question

A certain amount of money amounts to 4400 in 2 years and to 4600 in 3 years. Find the principal and rate of interest

Answer 1

principal interest = principle * rate * time / 100
interest of one year = 4600 - 4400 = 200
then principal = 200 * 100 / rate * 1
PR = 20000
I = P R T / 100
for first two years, 20000 * 2 / 100
 I = 400

principal = amount - interest.

Answer 2

Amount in 2 years = Rs 4400
Amount in 3 years. = Rs 4600
Therefore Interest in 1 year = Rs(4600-4400)
=Rs 200
Therefore Interest in 2 years = Rs (200 X 2)
= Rs 400
Therefore principal = Amount - Interest
= Rs(4400-400)
= Rs 4000

Therefore let rate of interest be = x % p.a
Therefore ATQ
200 = 4000 X 1 X x / 100
Therefore x = 5
Therefore Rate % per annum = 5 % per annum

Ans. Principal = Rs 4000
Rate = 5% per annum

I hope this helps.
Happy New Year.