You may also like

problem icon


What are the missing numbers in the pyramids?

problem icon

Paving the Way

A man paved a square courtyard and then decided that it was too small. He took up the tiles, bought 100 more and used them to pave another square courtyard. How many tiles did he use altogether?

problem icon


What would be the smallest number of moves needed to move a Knight from a chess set from one corner to the opposite corner of a 99 by 99 square board?

Adding and Multiplying

Age 11 to 14 Short Challenge Level:

Amy was asked to multiply a number by 8 and then add 5.
Instead, she added 8 to the number, then multiplied the result by 5.
This gave her 2015.

What would the answer have been if Amy had followed the instructions correctly?

This problem is adapted from the World Mathematics Championships
You can find more short problems, arranged by curriculum topic, in our short problems collection.