1. “Your licence number?” said Greg. “1089 seems a very ordinary number except it’s a perfect square.” Jim smiled, shaking his head. “It’s not that,” he replied. “If you multiply it by a certain whole number you get the same licence number backwards. Multiply by 9 and you get 9801.” “That’s good,” his friend exclaimed. “D’you think any other 4-digit number works that way, even if not for 9 times?” Well?

One other number: 2178 multiplied by 4

One other number: 3204 multiplied by 8

Two other numbers: 1698 multiplied by 6 and 2024 multiplied by 4