Grouping Goodies

Pat counts her sweets in different groups and both times she has some left over. How many sweets could she have had?

What Number?

I am less than 25. My ones digit is twice my tens digit. My digits add up to an even number.

Odd Tic Tac

An odd version of tic tac toe

The Set of Numbers

The Set of Numbers

Can you place the numbers from $1$ to $10$ in the grid (or matrix) below?

Now try putting the same numbers in this grid:

Why do this problem?

This problem is a good introduction to matrices. It provides experience in completing tables as well as offering plenty of number work.

Possible approach

Modelling how to fill in matrices like these might be a good place to start as pupils may not have encountered them before. You may find these sheets useful.

Key questions

Is this number odd or even?
Which tables will you find this number in?
How about going through the numbers in order, starting with $1$?
Is $1$ a multiple of $2$? Is it greater than $5$?

Possible extension

Learners could try a slightly more difficult problem using multiples Grouping Goodies or a much harder one with a table to complete, Mystery Matrix.

Possible support

Suggest using numbered counters and these sheets.