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If $120 doubles in approximately 13 years, what is the interest rate?

User TimWhiting
by
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1 Answer

7 votes

Answer:

33.3%

Explanation:

Simple Interest = Principal * Rate * Time/100

Amount = Principal + Interest

If $120 doubles in approximately 13 years, then the amount after 13years = 2*$120 = $240

Interest = $240-$120

Interest = $120

120 = 120*Rate * 13/100

1 = 13Rate/100

13rate = 100

rate = 100/3

rate = 33.3%

Hence the interest rate is 33.3%

User Successhawk
by
7.1k points