Question

a sim of money invested at compound interest amounts to 16500 in 1 year and to 19965 in 3 years find the rate percent and the original sum of money

Answer 1

Amount1 = 16500
Amount3= 19965.
Formula-
Amount1=P(1+r/100)^n.
n=no. of years
16500=P(1+r/100)^1

19965=P(1+r/100)^3

On diving them,
19965/16500=P(1+r/100)^3 / P(1+r/100)^1
[P gets canceled]

19965/16500= (1+r/100)^2

121/100=(1+r/100)^2

11/10= 1 + r/100

11-10/10 = r/100

1/10 x 100 = r

R= 10%

Therefore, original sum = 15000

Answer 2

Answer:

15000

Step-by-step explanation:

Amount1 = 16500

Amount3= 19965.

Formula-

Amount1=P(1+r/100)^n.

n=no. of years

16500=P(1+r/100)^1

19965=P(1+r/100)^3

On diving them,

19965/16500=P(1+r/100)^3 / P(1+r/100)^1

[P gets canceled]

19965/16500= (1+r/100)^2

121/100=(1+r/100)^2

11/10= 1 + r/100

11-10/10 = r/100

1/10 x 100 = r

R= 10%

Therefore, original sum = 15000