Here are a few doubles facts:
5+5=10
2+2=4
3+3=6
A double is simply a pair of identical numbers added together. There's a pair of doubles you can subtract 1 from to get 6+7, and there's a pair you can add 1 to get the same answer. What are those pairs?
Hint: If you take the example 3+4, you can either subtract 1 from the double 4+4 or add 1 to the double 3+3 to obtain your answer.
