Puzzles
A strange rule splits a troop of monkeys into two groups — how many monkeys in total?
In Bhaskara's classic version, the square of one-eighth of a troop of monkeys is playing in a forest, while the remaining twelve monkeys sit chattering on a nearby hilltop. How many monkeys are in the troop altogether?
Reveal the answer
There are two valid answers: 16 or 48 (both satisfy (x/8)^2 + 12 = x). Bhaskara himself noted the puzzle has two legitimate positive solutions, an early, explicit acknowledgment that a quadratic equation can have more than one right answer. It appears in the 'Lilavati,' the arithmetic section of Bhaskara II's 12th-century Sanskrit treatise 'Siddhanta Shiromani.'
— Bhaskara II, Lilavati — c. 1150 CE, from the Siddhanta Shiromani
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