In how many years will a sum placed at compound interest become 8 times itself, if it becomes twice itself in 6 years?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 18
At compound interest the amount is multiplied by the same factor in every equal period. The sum doubles in 6 years, so it doubles again in every further 6 years.
\(8=2\times2\times2\): the sum must double three times
Time \(=3\times6=18\) years