Algebra - Applications of Linear Equations

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Section 2.3 : Applications of Linear Equations

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1. A widget is being sold in a store for $135.40 and has been marked up 7%. How much did the store pay for the widget?

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Start Solution

We’ll start by letting $p$ be the price that the store paid for the widget. The widget has been marked up by 7% and so 0.07$p$ has been added to the original price, $p$.

The equation we get for this problem is then,

\[\begin{align*}p + 0.07p & = 135.4\\ 1.07p & = 135.4\end{align*}\] Show Step 2

To finish all we need to do is divide both sides by 1.07 to get the price the store paid for the widget.

\[p = 126.5421\]

So, with rounding the store paid $126.54 for the widget.