Question

Ronald can shovel the driveway in 2 hours, but if his brother Donald helps it would take 1 hours. How long, in hours and minutes, would it take Donald to shovel the driveway alone? Write your answer in mixed units

Answer 1

Given:

Ronald complete the job = 2 hours

With the help of Donald, then complete the job = 1 hours

Find:-

How long, in hours and minutes, would it take Donald to shovel the driveway alone?

Sol:-

Ronald can complete the job in 2 hours, so the unit rate is:

`=(1)/(2)`

Of the job per hour.

Let x be the unit rate of Donald.

So,

`(1)/(2)+x=(1)/(1)`

The value of "x" is:

`\begin{gathered} (1)/(2)+x=1 \\ \\ x=(1)/(1)-(1)/(2) \\ \\ x=(1)/(2) \end{gathered}`

So Donald has a unit rate of 1/2 which means we would complete the job in 2 hours, too