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We are asked to find the interest rate using simple interest. Therefore we would use the equation

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$\\displaystyle r=\\frac{c_1-c_0}{c_0}$

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where $r$ is the rate of return, $c_1$ is the final value of the investment and $c_0$ is the initial value of the investment.

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In our situation we have,

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$\\displaystyle r=\\frac{\\var{c1}-\\var{c0}}{\\var{c0}}$

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Calculating this we find

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\\begin{align}r&\\approx\\var{rdec}\\\\&=\\var{rrounded}\\%\\text{ (to 2 decimal places)}\\end{align}

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An investment of $\\$\\var{c0}$is made and$\\var{years}$years later it is worth$\\$\\var{c1}$. What was the rate of return?

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[[0]] $\\%$ (to 2 decimal places)

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