Problem: Each valve , and , when open, releases water into a tank at its own constant rate. The number of hours required with only valves and open is
Answer Choices:
A.
B.
C.
D.
E.
Solution:
Let , and denote the number of tankfuls of water delivered by valves , and respectively in one hour. Then
.
Sabtracting the sam of the last two equations from twice the first, gives so that tankful will be delivered by valves and in hours