Henry Ernest Dudeney/Puzzles and Curious Problems/156 - Multiplying the Nine Digits/Solution

Puzzles and Curious Problems by Henry Ernest Dudeney: $156$

Multiplying the Nine Digits

They were discussing mental problems at the Crackham's breakfast-table,

when George suddenly asked his sister Dora to multiply as quickly as possible:

$1 \times 2 \times 3 \times 4 \times 5 \times 6 \times 7 \times 8 \times 9 \times 0$

How long would it have taken the reader?

Solution

As long as it would take me to notice there is a $0$ amongst the multiplicands.

Wake up at the back.

Sources

• 1932: Henry Ernest Dudeney: Puzzles and Curious Problems ... (previous) ... (next): Solutions: $156$. -- Multiplying the Nine Digits
• 1968: Henry Ernest Dudeney: 536 Puzzles & Curious Problems ... (previous) ... (next): Answers: $141$. Multiplying the Nine Digits