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Brain Teasers and Puzzles



Puzzle Details

A large fresh water reservoir has two types of drainage system: small pipes and large pipes.

6 large pipes, on their own, can drain the reservoir in 12 hours.

3 large pipes and 9 small pipes, at the same time, can drain the reservoir in 8 hours.

How long will 5 small pipes, on their own, take to drain the reservoir?

Puzzle Copyright © Kevin Stone

hint answer

Puzzle Code = ZHRT = www.brainbashers.com/ZHRT