Question 266905
John can mow 3 yards in 2 hrs while sally can mow 4yards in 3hrs. Working together, how long would it take them to mow 2 yards?

John can mow yards at the rate of 3 yards/2 hours or 3/2 yards per hour.
Sally can mow yards at 4 yards/3 hours = 4/3 yards per hour.

Together then they mow at a rate of 3/2 + 4/3 yards per hour. If t is the time needed for them to mow 2 yards then we have:

2 = (3/2+4/3)*t

Solve the above for t.