Question

If Rs 640months to Rs 768 in 2years 6months what will Rs 850 amount to in 3 years at the same rate per cent per annum?

Answer 1

Principle = rs 640
Time = 2 years 6 months = 2 1/2 years = 5/2 years
Amount = rs 768
Let rate of interest be x%
So, S.I = PxTxR /100
=640 x X x 5/100 x 10
=16x
So, amount =P +S.I
=640 + 16x
Also,amount = rs 768
So,640+16x =768
16x = 768 - 640
X = 128/16
X = 8
So, rate of interest = 8%

In next part,
Given that,
Principle = rs850
Time = 3 years
Rate of interest per annum = 8%
Therefore, S.I = 850 x 3 x 8/100
=204
So, amount = P +S.I
=850 + 204
=rs 1054