13. A sum of money trebles itself in 8 years at compound interest. In how
many years will it become 27 times?
Answers
If the sum doubles (*2) in 15 years, then it to become 2*2*2 = 8 times as large it should double three times, so three 15 years time period are needed, which is 3*15 = 45 years.
Answer: C.
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according to this concept you can solve your question....esily
Answer:
The sum will become 27 times in 24 years
Step-by-step explanation:
Formula: R= 100[(n)^1/t -1] %
It is given that when the sum of money triples itself in 8 years
Therefore n=3 and t=8.
Substituting the values of n and t in the formula we get,
R = [100(3)^1/8 -1] ---equation 1
To find the the years it will take to become 27 times,
n = 27, t=?
Substituting in the formula,
R = 100 [(27)^1/t -1]% ----- equation 2
Substitute the value of R from equation 1 in equation 2 we get,
100 [(3)^1/8-1] = 100[(27)^1/t-1]
Cancelling 100 and -1 on both sides we get,
3^1/8 = 27^1/t
converting 27 in terms of 3
3^1/8 = 3^3/t ( since 3^3 =27)
1/8=3/t
1t =8*3
t= 24
The numbers of years it will take is 24 years.