Tap K can fill a tank in 8 hours and tap L can fill the same tank in 20 hours. In how many hours both tap K and L together can fill the same tank?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 40/7 hours.
| Understanding/Application |
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Let the capacity of the tank be 40 units (LCM of 8 and 20) Efficiency of Pipe K = 40/8 = 5 units per hour. Efficiency of Pipe L = 40/20 = 2 units per hour. They can fill the tank at 7 units per hour. |
| 40 units can be filled in = 40/7 hours |