Problem 23: Fill in the magic square. (Hint: every row, column and diagonal has the same sum.)

4 | ||

6 | ||

1 | 8 |

Predict: I predict I will have to use addition in this problem.

Clarify: I have no words, sentences or phrases that I need to clarify.

Find the big question: What are the missing numbers?

Solve: First, I need to work out what 4+6+8 equals. It equals: 18.

So, now I need to make every row, column and diagonal equal 18.

First I will start with 6 and 1. That equals 7, so I need 11 more to get to 18. So I write in 11 above 6.

So now I have 11 next to the four, and added together that equals 15, and I need 3 more to get to 18. So I write 3 next to 11.

Now I’ve got another row with 2 numbers. 3 and 8. That equals 11, and I need 7 more to get to 18.

Now I have a 6 and a 7, and that equals 13, and I need 5 more to get to 18.

Finally, I have a 4 and a 5 which equals 9, and there needs to be another 9 to get to 18.

4 | 11 | 3 |

5 | 6 | 7 |

9 | 1 | 8 |

Summarize: the mathematicians toolbox strategy I used in this sum was break the problem into manageable parts.