Doubling and halving strategy

 In class we learned a new strategy called Doubling and halving
when you do this strategy you look to see how you can make it easier 
For Example
5 x 48
you can half 48, which then becomes 24 and you can double 5 which then becomes 10
4 x 16
you can half 16, which then become 8 and you can double 4 which then becomes 8