Mathematics
Problem of The Day
2025
164

164

The hikers can proceed as follows:

  1. The 45 kg and 50 kg hikers cross the river together.
  2. The 45 kg hiker returns with the boat.
  3. The 80 kg hiker crosses the river alone.
  4. The 50 kg hiker takes the boat back.
  5. Finally, the 45 kg and 50 kg hikers cross the river together once more.

All three hikers successfully cross the river using this strategy while respecting the boat's 100 kg weight limit.

‍

Answer

Yes, possible!

SOLUTIOn

The hikers can proceed as follows:All three hikers successfully cross the river using this strategy while respecting the boat's 100 kg weight limit.

  1. The 45 kg and 50 kg hikers cross the river together.
  2. The 45 kg hiker returns with the boat.
  3. The 80 kg hiker crosses the river alone.
  4. The 50 kg hiker takes the boat back.
  5. Finally, the 45 kg and 50 kg hikers cross the river together once more.
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We hold our classes online or on-site on Saturdays at our branch in Pimlico Academy, London.
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What do you need to start learning online?
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The trial lesson is a 30-minute online session designed to get a sense of how your child approaches mathematical thinking and problem solving. (In practice, it often runs a bit longer if the student is engaged!)

We typically explore a range of fun and challenging problems drawn from competitions. We adapt the difficulty based on how the student responds, aiming to make it both accessible and stimulating.

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