In this activity, we will work out what goes in or what comes out of a doubling machine.
Here 6 x 2 = 12, so when 6 goes in, 12 comes out.
Also 12 ÷ 2 = 6, so when 12 comes out, 6 must have gone in.
Remember that:
Doubling is the same as multiplying by 2.
Halving is the same as dividing by 2.
Let's get started!