100 eggs, three prices, one buyer, and a bill of exactly 8 shillings 4 pence
A dairyman sold eggs at three prices: fivepence each, a penny each, and a halfpenny each. A customer bought some of each kind and left with exactly 100 eggs for exactly 8 shillings 4 pence — buying the very same number of eggs at two of the three prices. How many did he buy at each price?
Reveal the answer
10 eggs at 5d, 10 eggs at 1d, and 80 eggs at ½d: 10+10+80=100 eggs, and 50d+10d+40d=100d=8s 4d. From Henry Dudeney's Amusements in Mathematics (1917), puzzle No. 22.
— Henry Dudeney, Amusements in Mathematics — Thomas Nelson & Sons, 1917, Puzzle No. 22
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