Pump A can fill a tank of water in 5 hours. Pump B can fill the same tank in 8 hours. How long does it take the two pumps working together to fill the tank?(round your answer to the nearest minute).	Select
A) 3 hours 5 minutes
B) 4 hours 5 minutes
C) 5 hours 5 minutes
D) 6 hours 5 minutes
E) 7 hours 5 minutes
In 1 hour pump A can fill 1/5 of a tank and pump B can fill 1/8 of the same tank. So in 1 hour the two pumps working together can fill   1/5 + 1/8 = 13 / 40 of a tank   Since the rate of the two pumps working together is 13/40, the time t needed to fill the tank by the two pumps is found by solving   (13/40) t = 1   t = 40 / 13 = 39/13 + 1/13 hours   = 3 hours and (1/13)*60 minutes   = 3 hours 5 minutes (rounded to the nearest minute)   correct answer 3 hours 5 minutes
<result>A</result>
Pump A can fill a tank of water in 5 hours. Pump B can fill the same tank in 8 hours. How long does it take the two pumps working together to fill the tank?(round your answer to the nearest minute).