Question

It takes an older computer 4 times as long to send out a company’s email as it does a newer computer. Working together, it takes the two computers 12 minutes to send out the email. How long will it take the older computer to send out the email on its own? Do NOT do any rounding.

Answer 1

We will have the following:

`\begin{gathered} (1)/(x)+(1)/(4x)=(1)/(12)\Rightarrow(4)/(4x)+(1)/(4x)=(1)/(12) \\ \\ \Rightarrow(5)/(4x)=(1)/(12)\Rightarrow4x=60 \\ \\ \Rightarrow x=15 \end{gathered}`

So, it takes 15 minutes for the new computer; then the old computer will take 60 min.