SOLUTION: Can you help please! One pipe can fill a tank in 4 hours. A second pipe can fill it in 5 hours. A third pipe can fill it in 6 hours. How long would it take all three pipes to f

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Can you help please! One pipe can fill a tank in 4 hours. A second pipe can fill it in 5 hours. A third pipe can fill it in 6 hours. How long would it take all three pipes to f      Log On


   



Question 746597: Can you help please!
One pipe can fill a tank in 4 hours. A second pipe can fill it in 5 hours. A third pipe can fill it in 6 hours. How long would it take all three pipes to fill the tank working together?

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Add their rates of filling
1st pipe: ( 1 tank filled ) / ( 4 hrs )
2nd pipe: ( 1 tank filled ) / ( 5 hrs )
3rd pipe: ( 1 tank filled ) / ( 6 hrs )
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+1%2F4+%2B+1%2F5+%2B+1%2F6+=+1%2Ft+
Multiply both sides by +60t+
+15t+%2B+12t+%2B+10t+=+60+
+37t+=+60+
+t+=+1.622+ hrs
+.622%2A60+=+37+
All 3 pipes working together take 1 hr and 37 min