Question

A certain sum of money amouts to rs 10080 in 5 years at 8% find principle

Answer 1

A certain sum of money amounts to Rs.4800 in 5 yr at 4% per annum.In how many years will it amount to Rs.16000 at the same rate of interest?


Simple interest, SI  = PRT/100 (P = Principal, R = Rate of Interest, T = Time in years)

The sum amounts to Rs.4800 in 5 yr at 4% per annum. Simple interest = (4800-P)

P×4×5

100=(4800−P)

P×4×5100=(4800−P)


20P = 480000 - 100P
120P = 480000 
P = Rs.4000

Let required time  = n years.

Simiple interest in n years=  16000 - P = 16000 - 4000 = Rs.12000

4000×4×n

100

4000×4×n100

= 12000
n =