An amount becomes 4 times in 7 years when invested under SI at a certain rate. In how many years will the amount become 16 times of the original amount at the same rate?
40 Years
45 Years
35 Years
25 Years
Explanation:
If we invest Rs.100 in bank it becomes Rs.400 in 7 years.
Interest earned on the principal is equal to Rs.300.
In other words in 7 years bank gives Rs.300 if we invest Rs.100.
Now if we want to earn 16 times of the investment, then bank has to give 1500 interest for Rs.100.
As we know that bank gives Rs.300 for 7 years, We must keep our money in bank for 35 years to get an interest of Rs.1500. So answer is 35 years.
If we invest Rs.100 in bank it becomes Rs.400 in 7 years.
Interest earned on the principal is equal to Rs.300.
In other words in 7 years bank gives Rs.300 if we invest Rs.100.
Now if we want to earn 16 times of the investment, then bank has to give 1500 interest for Rs.100.
As we know that bank gives Rs.300 for 7 years, We must keep our money in bank for 35 years to get an interest of Rs.1500. So answer is 35 years.