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

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

Explanation:

Hi

Leon do the work in 17 hours that means the rate of his work is
`(1)/(17) work/hr`, so he do
`(2)/(17)` of the work in two hours, therefore Michael do the other
`(15)/(17)` of the work, thus Michael rate will be
`(15)/(17) /(1)/(2) =(30)/(17) work/hour`.

So it takes Michael
`1h+(4)/(17)h` to complete the work, or
`(4h)/(17) * (60min)/(1hour) =14(2)/(17) min\\\\(2)/(17) min * (60 secs)/(1min)=7secs`

`1h \ 14 min \ 7secs`