Answer
She must bowl at least 158 to have an average of at least 150 for the three games.
Work Step by Step
Let x represent her score in the third game.
Her average will be $\frac{132\ +\ 160\ +\ x}{3}$.
This average should be at least 150.
So, we solve the following inequality.
$\frac{132\ +\ 160\ +\ x}{3}$ $\geq$ 150.
Multiply both sides by 3.
132 + 160 + x $\geq$ 450
x $\geq$ 450 - 160 - 132
x $\geq$ 158
So, she must bowl at least 158 to have an average of at least 150 for the three games.
