Henry Ernest Dudeney/Puzzles and Curious Problems/166 - Hens and Tens

by : $166$

 * Hens and Tens
 * If ten hen-pens cost ten and tenpence (that is, $10 \shillings 10 \oldpence$),
 * and ten hens and one hen-pen cost ten and tenpence,
 * what will ten hens without any hen-pens cost?