Problema Solution

You have saved $7,000 towards the purchase of a car costing $9,000. How long will the $7,000 have to be invested at 9% compounded monthly to grow to $9,000? (Round up to the next-higher month if not exact.)

Answer provided by our tutors

P = $7,000

r = 0.09 or 9%

A = $9,000

t = the time in months

A = P(1 + r/12)^t

7000(1 + 0.09/12)^t = 9000

1.0075^t = 9000/7000

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click here to see the equation solved for t

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t = 33.63 months or 34 months rounded to the next higher month

The money should be compounded monthly for 34 months.