- Look for different ways for each number.
- What extra key would you need to make 11 with four fours?
- I made 11 numbers between 10 and 50 - can you find them? Maybe there are more.
- When don't you need to use the "=" along the way?
- Try the puzzle on a basic calculator - does it work the same as the game?
- Why did I insist on getting the numbers in order?
- What is the biggest number you can make?
- How about the smallest?
- Make up your own puzzle.