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 Question from Jackie: If I make \$12.00 per hour and I cover 750 sq ft in one hour, how much money do I make per sq ft?

Hi Jackie,

The units tell you what to do. You have dollars per hour, square feet per hour and you want dollars per square foot. That is you have

$\frac{\}{hr}, \frac{\mbox{ square feet}}{hr} \mbox{ and you want } \frac{\}{\mbox{square foot}}.$

But if you have

$\frac{\}{hr} \times \frac{hr}{\mbox{ square foot}}.$

Then the hours cancel and you have

$\frac{\}{\mbox{ square foot}}.$

Hence

$12 \frac{\}{hr} \times \frac{1}{750} \frac{hr}{\mbox{ square foot}} = \frac{12}{750} \frac{\}{\mbox{ square foot}}.$

I hope this helps,
Penny

Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.