Question

It takes Leon 17 hours to seal his driveway working by himself. If Michael helps Leon, they can seal the driveway in 2 hours. How long would it take Michael to seal the driveway close?

Answer 1

Answer:

It takes Michael 1 hour, 14 minutes and 7 seconds to seal the driveway close

Step-by-step explanation:

Hi

Leon do the work in 17 hours that means the rate of his work is $\frac{1}{17} work/hr$, so he do $\frac{2}{17}$ of the work in two hours, therefore Michael do the other $\frac{15}{17}$ of the work, thus Michael rate will be $\frac{15}{17} \div\frac{1}{2} =\frac{30}{17} work/hour$.

So it takes Michael $1h+\frac{4}{17}h$ to complete the work, or $\frac{4h}{17} \times \frac{60min}{1hour} =14\frac{2}{17} min\\\\\frac{2}{17} min \times \frac{60 secs}{1min}=7secs$

$1h \ 14 min \ 7secs$