Mathematics
NULL
Medium
Question
Two pipes fill a tank in 20 and 24 minutes; a waste pipe empties 3 gallons per minute. All three together fill the tank in 15 minutes. The capacity of the tank is?
A
60 gallons
B
100 gallons
C
120 gallons
✓ Official correct answer
D
180 gallons
Community credibility
Registered members can vote for the answer they believe is correct today and explain why. If the facts change after an election or news event, suggest a new option so others can vote it up.
A
60 gallons
No member explanations yet for this option.
B
100 gallons
No member explanations yet for this option.
C
120 gallons
No member explanations yet for this option.
D
180 gallons
No member explanations yet for this option.
Explanation
1/20 + 1/24 − 3/C = 1/15 ⇒ 3/C = 1/40 ⇒ C = 120 gallons.