## Algebra: A Combined Approach (4th Edition)

$\frac{2+x}{5+5}=\frac{5}{10}$ $\frac{2+x}{10}=\frac{5}{10}$ $2+x=5$ $x=5-2$ $x=3$
When solving an equation to answer Qn 3, we have to ensure that the total number of shots made divided by (the total number of shots made + the total number of shots missed) is 50%, or $\frac{5}{10}$. Hence, we use the following equation: $\frac{2+x}{5+5}=\frac{5}{10}$ $\frac{2+x}{10}=\frac{5}{10}$ $2+x=5$ $x=5-2$ $x=3$ We cannot try to solve using an equation to get an 80% shooting success rate if we shoot 5 more shots since we have to make 8 out of 10 shots to have an 80% shooting success rate within 10 shots, and we already missed 3 shots during the first 5 shots so the best we can get is a 70% shooting success rate if we make all 5 of the next shots.