# How do they get everyone across the river in the fastest time without breaking the rules?

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There are four people in an adventure race that need to get across a lake. They have a small canoe. The rules say that only the slowest person in the canoe can paddle, only one or two can be in the canoe at a time, and they must all cross in the canoe. From practice, they know that: Arnav can paddle across in 1 minute. Bilal can paddle across in 2 minutes. Suresh can paddle across in 5 minutes. Mohan can paddle across in 10 minutes.
How do they get everyone across the river in the fastest time without breaking the rules?

posted Jun 15, 2015

+1 vote

First run Arnav + Bilal (2 minutes)
Arnav rows back ( 1 minute)
Second run Suresh + Mohan (10 minute)
Bilal rows back (2 minutes)
Third run Arnav + Bilal (2 minute)
Total = 17 minutes

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