SOLUTION: 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?

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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?
Found 2 solutions by dabanfield, josmiceli:
Answer by dabanfield(803) About Me  (Show Source):
You can put this solution on YOUR website!
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.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
If John can mow 3 yards in 2 hours, then
he can mow 1 yard in 2/3 hr, because
(1 yards)/(2/3)hrs = 3 yard/2 hrs
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If Sally can mow 4 yards in 3 hrs, then
she can mow 1 yard in 3/4 hrs, since
(1 yards)/(3/4)hrs = 4 yard/3 hrs
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Working together, I add their rate of working
3%2F2+%2B+4%2F3+=+2%2Fx
Multiply both sides by 6x
9x+%2B+8x+=+12
17x+=+12
x+=+12%2F17 hrs