SOLUTION: Rowland can mow his yard in 21 minutes, It takes Don 28 minutes to mow the same lawn. How long should it take both of them,working together, to mow the yard?

Question 265615: Rowland can mow his yard in 21 minutes, It takes Don 28 minutes to mow the same lawn. How long should it take both of them,working together, to mow the yard?
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!

If A can do a job in x time periods, then A can do

of the job in 1 time period. Likewise, if B can do the same job in y time periods, then B can do

of the job in 1 time period.

So, working together, they can do

of the job in 1 time period.

Therefore, they can do the whole job in:

time periods.

John

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