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Puzzle for Today

Puzzle No. 505 – Wednesday 19 June

Claire owns some ducks, and notices that their large clutch of 24 eggs is beginning to hatch. She decides to give them some space and return three hours later. The ducklings hatch out at a steady rate of 8 eggs per hour. However, at the end of each hour a fox visits the clutch and eats half of the hatched ducklings. How many ducklings does Claire discovery upon her return?

Today’s #PuzzleForToday has been set by Dr Geoff Evatt, School of Mathematics, University of Manchester

In the first hour 8 eggs hatch and half of the ducklings (4) are eaten. In the second hour 8 more ducklings hatch to join the remaining 4 ducklings, making 12 in total. But the fox eats half (6) of them. In the third hour 8 more ducklings hatch, joining the remaining 6, making a total of 14. But again the hungry fox gobbles up half of those, leaving only 7 left.... Lucky old fox.

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