Users receive reward points for every dollar charged to their credit card. Different numbers of points are received for different categories of purchases, as shown below.

$$ \begin{array}{|c|c|} \hline \text{Category} & \text{Points per dollar spent} \\ \hline \text{App store} & 5 \\ \hline \text{Utilities} & 3 \\ \hline \text{Other charges} & 1 \\ \hline \end{array} $$

Suppose a certain individual spent $50 on the app store, $230 on utilities, and $450 on other items. If the individual charged these amounts to their credit card, which is closest to the percentage of the reward points in these three categories would they receive from utilities?

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We can calculate the number of points an individual would receive from their purchases.

$$ \begin{array}{|c|c|c|c|} \hline \text{Category} & \text{Points per dollar spent} & \$ \text{ Spent} & \text{Points received}\\ \hline \text{App store} & 5 & \$50 & 5\cdot50=250\\ \hline \text{Utilities} & 3 & \$230 & 3\cdot230=690\\ \hline \text{Other charges} & 1 &\$450 & 1\cdot450=450\\ \hline \end{array} $$

The percentage of points from utilities is:

$$ \frac{\text{points from utilities}}{\text{total points}} $$ $$ =\frac{690}{250+690+450} $$ $$ =\frac{690}{1390} $$ $$ \approx 0.496 $$ $$ =\boxed{50\%} $$