SOLUTION: If a machine A makes 1000 gidgets in 4 hours, and machine B makes 1000 gidgets in 8 hours, how long will it take both machines to make 1000 gidgets??

Question 245846: If a machine A makes 1000 gidgets in 4 hours, and machine B makes 1000 gidgets in 8 hours, how long will it take both machines to make 1000 gidgets??
Found 2 solutions by nerdybill, Alan3354:
Answer by nerdybill(7384) (Show Source): You can put this solution on YOUR website!
If a machine A makes 1000 gidgets in 4 hours, and machine B makes 1000 gidgets in 8 hours, how long will it take both machines to make 1000 gidgets??
.
Let x = time it takes for both machines to make 1000 gidgets
then
x [1000/4 + 1000/8] = 1000
Multiplying both sides by 8:
x [2000 + 1000] = 8000
x [3000] = 8000
x = 8000/3000
x = 8/3 hours
or
x = 2 hours and 40 minutes

Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Use the shortcut product/sum
= 8*4/(8+4) = 32/12
t = 8/3 hours = 2 hr 40 minutes
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