SOLUTION: Pump A can unload a tanker in 15 hours, Pump B can unload the same tanker in 25 hours. Because of an approaching storm, both pumps are used to empty the tanker. If the pumps begi

Question 76963: Pump A can unload a tanker in 15 hours, Pump B can unload the same tanker in 25 hours. Because of an approaching storm, both pumps are used to empty the tanker. If the pumps begin at 2:30 a.m., what time will the job be complete?
Answer by ptaylor(2198) (Show Source): You can put this solution on YOUR website!
Let x=number of hours that it takes both pumps to unload all the tanker
Pump A unloads at the rate of 1/15th tanker per hour
Pump B unloads at the rate of 1/25th tanker per hour
Pump A + Pump B together unloads at the rate of 1/15+1/25 tanker per hour:
1/15=5/75
1/25=3/75
5/75+3/75=8/75 tanker per hour
So, Pump A + Pump B together unloads at the rate of 8/75 tanker per hour

Now we know that the rate that both unload times number of hours to unload the whole thing equals the whole thing off loaded. So our equation to solve is:

(8/75)x=75/75 (Note: 75/75 denotes all the tankers load)
multiply both sides by 75 and we get
8x=75
x=9.375 hours-9h 22.5m
And 2:30 am plus 9h 22.5m=11:52.5 AM------------------answer

Hope this helps----ptaylor
RELATED QUESTIONS
25 men can unload a truck in 2 hours.how many hours should it take 15 men to unload the... (answered by Edwin McCravy)

Hello Tutors, I am having trouble answering two questions: 1. An oil tanker can be (answered by addingup)

And oil tanker can be emptied by the main pump in five hours in auxiliary pump can empty... (answered by ikleyn,MathTherapy,greenestamps)

an oil tanker can be emptied by the main pump in 4 hours. an auxiliary pump can empty the (answered by stanbon)

An oil tanker can be emptied by the main pump in 5 hours. An auxilary pump can empty the... (answered by ankor@dixie-net.com,Alan3354)

please help an oil tanker can be emptied by the main pump in 4 hours. an auxiliary pump... (answered by Theo)

an oil tanker can be emptied by the main pump in four hours. an auxilary pump can empty... (answered by scott8148,Edwin McCravy)

An oil tanker can be emptied by the main pump in 4 hours. An auxiliary pump can empty the (answered by ankor@dixie-net.com)

An oil tanker can be emptied by the main pump in 4 hours. An auxiliary pump can empty the (answered by lwsshak3)