A hallway measuring 90 feet x 7 feet requires 1/2 a fluid ounce of cleaning solution per square foot. How much cleaning solution is required to clean the hallway?

First, find the area of the hallway.

$$Area=length*width$$

$$A=90*7$$

$$A=630$$

Now you know there are 630 square feet to be cleaned. To find the amount of cleaning solution needed, multiply this number by 1/2.

$$Solution=area* \frac{1}{2}$$

$$S=630* \frac{1}{2}$$

$$S= \frac{630}{2}$$

$$S=315$$

$$90*7 = 630ft ^{2} \\ \\ 1/2 floz ->1 ft^{2} \\ \\ 630/2=315 \\\\\boxed{315}$$