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nydimaria [60]
2 years ago
7

27. The interest rate that doubles a sum in 10 years isa) 12%b) 11%c) 10%d) 9%​

Mathematics
1 answer:
avanturin [10]2 years ago
5 0

Answer:

Interest rate of 7%.

Step-by-step explanation:

The compound interest formula is given by:

A(t) = P(1 + \frac{r}{n})^{nt}

Where A(t) is the amount of money after t years, P is the principal(the initial sum of money), r is the interest rate(as a decimal value), n is the number of times that interest is compounded per year and t is the time in years for which the money is invested or borrowed.

In this question:

We want to find t for which A(t) = 2P when n = 1, t = 10. So

A(t) = P(1 + \frac{r}{n})^{nt}

2P = P(1 + r)^{10}

(1 + r)^10 = 2

\sqrt[10]{(1 + r)^10} = \sqrt[10]{2}

1 + r = 1.07

r = 0.07

So a interest rate of 7%.

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Answer:

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