# Got It

Got It is an adding game for two players. You can play against the computer or with a friend.

Rules:

The first player chooses a whole number from 1 to 4.

Players take turns to add a whole number from 1 to 4 to the running total.

The player who hits the target of 23 wins the game.

Here is a scoresheet from my game against the computer.

Can you work out the missing numbers?

Who won the game?

Play the game a few times against someone at home or over the phone, or play against the computer here: https://nrich.maths.org/gotit/. Record each game in a table like the one above.

The main goal of this activity is to try and find a winning strategy.

• You might already have an inkling of what a winning position looks like – if so, write it down now.

Alternatively, you might have spotted that there was some position that was impossible to win from. This is especially likely to be the case if you played against the computer, which always plays the best possible move. However, it CAN be beaten.

• Look at the tables you made in the first task. Highlight any totals that appear in every table where you won, and highlight any totals that appear in every table where you lost.
• Are there any totals that seem to always lead to you winning or losing?

Here are some screenshots from games against the computer.

• Which of these positions can you definitely win from?
• Which will the computer definitely win from?
• What stepping stones should you try to hit on your way to 23 if you want to win?

Play the game a few more times.Can you come up with a winning strategy?

• Describe a strategy that will always beat the computer.