Question

Working together, Adam and Pranav can mop a warehouse in 4.63 hours. Had he done it alone it would have taken Pranav 11 hours. How long would it take Adam to do it alone?

Answer 1

`8hours`

1)

Note that the more people work together the less time they spend.

This is a question about Proportions, Inverse variation. So let's set the ratios and the proportion given these data.

So we can write out the following ratios:

`\begin{gathered} (1)/(x)+(1)/(11)=(1)/(4.63) \\ \\ (x+11)/(11x)=(1)/(4.63) \\ \\ 4.63(x+11)=11x \\ 11x=4.63(x+11) \\ 11x-4.63x=11 \\ 6.37x=11 \\ (6.37x)/(6.37)=(11)/(6.37) \\ x=7.99\approx8 \end{gathered}`

So, it would take 8 hours for Adam to do it alone.