Question 608427
    Two drainpipes working together can drain a pool in 8 hours. Working alone the smaller pipe would take 12 hours longer than the larger pipe to drain the pool. How long would it take the smaller pipe to drain the pool?
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Let x = time (hours) for smaller pipe to drain pool alone
then
8(1/12 + 1/x) = 1
multiplying both sides by 12x:
8(x + 12) = 12x
8x + 96 = 12x
96 = 4x
14 hours = x