Question

a sum of money placed at ci double itself in 5 years it will amount to 8 times itself at same rate of interest in how many years​

Answer 1

answer:

 let sum=P

Time=2 Years

Amount=2P

According to the question

⇒P(1+  

100

r

​  

)  

5

=2P

⇒(1+  

100

r

​  

)  

5

=2

Cubic both side we gets

⇒(1+  

100

r

​  

)  

15

=8

⇒P(1+  

100

r

​  

)  

15

=8P

Hence,in 15 Years amount to eight times itself