A sum of money invested at 10% p.a. amounts to rupees 6500 in 3 years.

1.	A sum of money invested at 10% p.a. amounts to rupees 6500 in 3 years. What will it amount to in 2 years at 8% p.a. simple interest?
Answer» LET P be the principle amount case 1 given rate = 10% PER annum time = 3 YRS FINAL amount or sum = Rs. 6500 => PRINCIPLE amount + simple interest = Rs.6500 => P + (P x 10% x 3) = 6500 => P + 0.3 P = 6500 => 1.3 P = 6500 => P = 6500/1.3 => P = 5000 case 2 principle = Rs. 5000 rate = 8% time = 2 yrs S.I = Principle x rate x time = 5000 x 8% x 2 = Rs. 800 final Amount or sum = Rs. ( 5000 + 800) = Rs. 5,800

A sum of money invested at 10% p.a. amounts to rupees 6500 in 3 years. What will it amount to in 2 years at 8% p.a. simple interest?

Answer»

FINAL amount or sum = Rs. 6500

=> PRINCIPLE amount + simple interest = Rs.6500

=> P + (P x 10% x 3) = 6500

=> P + 0.3 P = 6500

=> 1.3 P = 6500

=> P = 6500/1.3

=> P = 5000

principle = Rs. 5000

rate = 8%

time = 2 yrs

S.I = Principle x rate x time

= 5000 x 8% x 2

= Rs. 800

final Amount or sum = Rs. ( 5000 + 800)

= Rs. 5,800