# Interest Rate Growth

Please include a formula for the calculations, along with an explanation of how to work out the problem.

How long will it take for $400 to grow to $1,000 at the interest rate specified?

a) 4 percent

b) 8 percent

c) 16 percent

https://brainmass.com/economics/finance/interest-rate-growth-18715

#### Solution Preview

You did not specify if the interest applied is simple or compounded..I am going to do the calculations for both.

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<br>1. Simple Interest

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<br> Let S be the total after the time n ...

#### Solution Summary

How long will it take for $400 to grow to $1,000 at the interest rate specified?

$2.49