Directions: Using the digits 1 through 9, once each, fill in the blanks so that the statement is true. Can you find more than one?
What numbers do you think would be too large? What do you think would be too small?
6C3=20, 7C2=21, 7C5=21, 8C2=28, 8C6=28
Source: Kerri Swails, Mark Alvaro