What's Left?

Use this grid to shade the numbers in the way described. Which numbers do you have left? Do you know what they are called?
Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving
Being curious Being resourceful Being resilient Being collaborative


Here is a grid showing the numbers $1-20$:

Image
What's Left?

Start with the first red number, $2$. Now, look along the top row of the grid to the next number, $3$.

Can you share $3$ exactly between $2$?

If the answer is yes then shade in the $3$ box. If the answer is no, leave it.

Now take the next number, $4$. Can you share $4$ exactly between $2$?

Again, if you can, shade the box with $4$ in it. Carry on doing the same with all the numbers.

Now do the same with the next red number, $3$. Look along the row for the next number, $4$ and shade all the numbers that will share exactly between $3$.

Now try with $4$ and with $5$.

Which numbers do you have left?