### 25! (Game)

Lets play a number game. You can play it in the box on the right. The goal of '25' is to make rows that add up to... you guessed it, 25!

In the normal 'play' mode, press space bar and add up the dice rolls. Put this number somewhere on the board. If you have 4 numbers in one row, try to work out in your head what the last number needs to be.

If you hold down the 'shift' key and click on a square, you can add a 'reminder' of what you need to put in that square to make 25 (up to 3 digits). Hit enter to confirm this number or escape to clear the square.

Play the game below:

### What's up with the weird dice system?

Did you notice that if a dice lands on 6 it is rolled again? No 6's are allowed. Did you also notice that 1 is always taken away from the total (one of them will 'roll back' one number)?

Think about what the chance is of rolling a 5 using this system? How about a 3? What about the other numbers? How could you work it out exactly? Filling in the chart may help.

Why do you think Mr L set it up this way?