9514 1404 393
Answer:
11 years, 7 months
Explanation:
When the investment reaches its desired value, it will be 3 times the original amount. So, we are looking for the number of half-month periods (n) of compounding such that ...
(1 +0.095/24)^n = 3
Taking logarithms, we have ...
n·log(1.003958333...) = log(3)
n = log(3)/log(1.009358333...) ≈ 278.09
This is 278.09/24 ≈ 11.59 years.
It will take about 11 years and 7 months for the investment to reach the desired value.
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Additional comment
The amount will be about tzs 2,758 short after 11 years 7 months. It will exceed the desired amount after 2 more days' interest is added.