Two hoses are pouring water into an empty pool. Hose 1 alone would fill up the pool in 6 hours. Hose 2 alone would fill up the pool in 9 hours. How long would it take for both hoses to fill up two-thirds of the pool? Answers.
A) 5/12 hours
B) 5/8 hours
C) 8/5 hours
D) 12/7 hours
E) 12/5 hours
Hose 1 would fill the pool alone in 6 hours   i.e. 1 Hour work of Hose 1 = 1/6   Hose 2 would fill the pool alone in 9 hours   i.e. 1 Hour work of Hose 2 = 1/9   i.e. 1 Hour work of Hose1 and Hose2 together = (1/6)+(1/9) = (5/18)   i.e. (5/18) work can be finished by Hose1 and Hose2 together in 1 hour   i.e. (2/3) work can be finished by Hose1 and Hose2 together in 1*(18/5)*(2/3) = 12/5 hour   Answer: Option 12/5 hours
<result>E</result>
Two hoses are pouring water into an empty pool. Hose 1 alone would fill up the pool in 6 hours. Hose 2 alone would fill up the pool in 9 hours. How long would it take for both hoses to fill up two-thirds of the pool?