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 Question from Jean, a student: If the yearly income from an investment is $30 and the annual interest rate is 12%,what is the original investment? Hi Jean, If the annual interest rate is 12% and you invested$\$400$ then the income at the end of the year would be

$0.12 \times \$400 = \$48$

You don't know the amount invested so call it $P$. You know the income at the end of the year is $\$30$so the expression in this case is$ 0.12 \times \$P = \$30$Solve for$P\$.

Penny

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