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a sum doubles itself in a year at certain rate compounded annually in how many years will it become 6 times

User CH Wing
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48 years will it become 16 times Option 3 is the right choice.

The sum of money doubles at compound interest in 6 years. In how many years will it become 16 times? Let's denote the principal amount as P.

If the principal amount doubles in 6 years, then after 6 years, it will be worth 2P. If it becomes 16 times the original amount after a certain number of years, then it will be worth 16P.

We can set up an equation to represent this situation:

16P = 2P(1 + r/100)^n

where r is the annual interest rate and n is the number of years.

Dividing both sides by 2P, we get:

8 = (1 + r/100)^n

Taking the natural logarithm of both sides, we get:

ln 8 = n ln(1 + r/100)

Solving for n, we get:

n = (ln 8) / (ln(1 + r/100))

We know that the principal amount doubles in 6 years, so we can plug in r = 100/6 and P = 1:

n = (ln 8) / (ln(1 + 100/600)) ≈ 48.08

Since we're dealing with time, we round up to the nearest whole year, so the answer is 48 years. Option 3 is the right choice.

Question:-

The sum of money doubles at compound interest in 6 years. In how many years will it become 16 times?

1. 16 years

2. 24 years

3. 48 years

4. 96 years

User JakubW
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