Question

A sum of amount as r% compound interest doubles in 3 years. In 9 years it will be k times of the original
principal. Find the value of (K^2 + 1).
please give correct answer i will mark you brainiest pls help me ​

Answer 1

Step-by-step explanation:

ANSWER

Let principal=p, rate %=R%

t=4 years

∴ Amount=2p

Case I,

2P=P(1+100R)4

2=(1+100R)4 …..(1)

Case II,

Let after t years it will be 8 times

8p=p(1+100R)t

23=(1+10R)t

By using equation (1) & (2)

(1+100R)12=(1+100R)t

By comparing both sides

t=12 years.