Directions: I picked 3 dominoes out of a bag and they all had exactly 10 pips, but the same number was not on both sides of any of the dominoes.
Show 3 dominoes I could have picked.
If one side of the domino had __ pips, how many pips were on the other side if I had 10 pips altogether?
1 and 9
2 and 8
3 and 7
4 and 6
Source: Brian Kelley