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What interest rate compound monthly is required for an $8500 investment to triple in 5 years

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Final answer:

To find the interest rate required for an $8500 investment to triple in 5 years when compounded monthly, we can use the formula: A = P(1 + r/n)^(nt). Plugging in the values, we find that an interest rate of approximately 9.54% compounded monthly is required for the $8500 investment to triple in 5 years.

Step-by-step explanation:

To find the interest rate required for an $8500 investment to triple in 5 years when compounded monthly, we can use the formula:

A = P(1 + r/n)^(nt)

where:

  • A = final amount
  • P = principal amount
  • r = annual interest rate (expressed as a decimal)
  • n = number of times interest is compounded per year
  • t = number of years

In this case, P = $8500 and A = $8500 * 3 = $25500. Let's assume the interest rate is 'r' and the compounding frequency is 'n = 12' (monthly).

Plugging in the values, we get:

$25500 = $8500(1 + r/12)^(12*5)

Solving for 'r', we have:

(1 + r/12)^(60) = 3

To find the value of 'r', we need to take the 60th root of both sides:

(1 + r/12) = 3^(1/60)

Simplifying, we have:

1 + r/12 = 1.079460507 = 1.0795

Subtracting 1 from both sides, we get:

r/12 = 0.0795

Multiplying both sides by 12, we have:

r = 0.954

Therefore, an interest rate of approximately 9.54% compounded monthly is required for the $8500 investment to triple in 5 years.

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