A student heading to an early morning study session decides to stop and get donuts for everyone. The donut shop sells donut by the half dozen (6), the bakers dozen (13), or in a box of 20. What is the largest number of donuts the student CANNOT purchase using only these three purchasing options?

Note: you must give your answer and explain how you found it. Answers without reasons will receive 0 points.

Solutions will be accepted till 5 PM Friday, December 9th. You can give your solution either to Dominique Banner or to Maria Nogin (PB 341; slip your paper under the door if no one is in).

Please write on your paper:

• your name
• e-mail address
• date and time of submission

Questions? Email Dominique Banner at dbanner@csufresno.edu