Calculate the following: (−10) × (5 − 2) and (−10) × (2 − 5).

(−10) × (5 − 2) = (−10) × 3 = −30

(−10) × (2 − 5) = (−10) × (−3) = 30

The first calculation is a negative number multiplied by a positive number and is negative, the second calculation is a negative number multiplied by a negative number and is positive.

A lottery scratch game would be won if the card revealed a temperature lower than −8 degrees centrigrade. A gambler bought a card which revealed −6 degrees. She thought she had won, the shopkeeper thought she had won, but Camelot thought she had lost. Who was right?

Camelot were right. Minus eight is a smaller number than minus six. If we take away eight, we lose more than if we take away six. The number line shows this:

smaller ←   . . .   −10   −9   −8   −7   −6   −5   −4   −3   −2   −1   0   1   2   3   4   5   6   7   8   9   10   . . .   → bigger

She said "I phoned Camelot and they fobbed me off with some story that −6 is higher — not lower — than −8 but I'm not having it."

This story made the national news, e.g. Private Eye number 1198, 23 November 2007.