Science Puzzle

The Desert Pack

Scientific Thinking Charge ⚡⚡
Traveller A 5 bottles Stranger pays 8 coins Traveller B 3 bottles All three share the 8 bottles equally. How should the 8 coins be split? B says: split 5 : 3 (who brought what) A says: that is wrong (who gave what?)
Fig. 1: Sharing equally does not mean each traveller gave the stranger the same amount.

Two travellers cross a desert. Traveller A has 5 bottles of water and Traveller B has 3. A stranger joins them and all three share the water equally across the whole journey.

At the end, the stranger pays 8 coins for his share. Traveller B says they should split the payment 5 to 3. Traveller A disagrees. Who is right, and what is the correct split?

The Answer

Traveller A is right. The correct split is 7 coins to A and 1 coin to B, not 5 and 3.

Each person drank an equal share of the 8 bottles, which is 8 ÷ 3 = 2⅔ bottles each. Traveller A contributed 5 bottles but consumed 2⅔, so he effectively gave the stranger 5 − 2⅔ = 2⅓ bottles. Traveller B contributed 3 but consumed 2⅔, so he gave the stranger only 3 − 2⅔ = ⅓ of a bottle.

The ratio of their contributions to the stranger is 2⅓ to ⅓, which simplifies to 7 to 1. A 5:3 split counts who brought the most, not who gave the most to the stranger. Reframing the question precisely reveals the answer.

The principle: Reframing perspective. Defining the question precisely changes the answer. The split is not who brought the most, but who gave the most to the person paying.