At McDonald's, you can order McNuggets in boxes
of 6, 9, or 20.

By ordering 2 boxes of 6, you can get 12. But you can not order 13, since no combination of 6, 9, and 20 adds up to 13.

What is the greatest number of McNuggets that you can not order?


Answer: 43 McNuggets.
44 = 4 x 6 + 20
45 = 3 x 9 + 3 x 6
46 = 2 x 20 + 6
47 = 3 x 9 + 20
48 = 8 x 6
49 = 9 + 2 x 20
You can get all numbers greater than 49 by adding 6 to the numbers above.

Correctly solved by:

1. Kelly Harris Winchester, VA
2. Matt Leatherman Winchester, VA
3. Claire Rezba Winchester, VA