Question

A copy machine makes 28 copies per minute. How long does it take to make 133 copies?

Answer 1

??

Answer 2

the rate of copies is \[r\left[\frac{\text{copies}}{\text{minute}}\right]=\frac {C[\text{copies}]}{t[{\text{min}}]}\]

\[\text{rate of copy machine}\quad r\left[\frac{\text{copies}}{\text{minute}}\right]=\quad28\left[\frac{\text{copies}}{\text{minute}}\right]\]

Answer 3

\[r\left[\frac{\text{copies}}{\text{minute}}\right]=\frac {C[\text{copies}]}{t[{\text{min}}]}\]
\[r=\frac Ct\]
\[t=\frac{C}{r}\]

Answer 4

\[t[{\text{min}}]=\frac {C[\text{copies}]}{r\left[\frac{\text{copies}}{\text{minute}}\right]}=\frac {133[\text{copies}]}{28\left[\frac{\text{copies}}{\text{minute}}\right]}=\]