Solutions to Exercises in chapter 1 – Sentential Logic – of How To Prove It by Daniel J Velleman.
Problem (2): Analyze the logical form of the following statements:
(a) Either John and Bill are both telling the truth, or neither of them is.
(b) I’ll have either fish or chicken, but I won’t have both fish and mashed potatoes.
(c) 3 is a common divisor of 6, 9, and 15.
Solutions:
(a) 
J stands for “John is telling the truth”, and
B stands for “Bill is telling the truth”.
(b) 
F stands for “I’ll have fish”,
C stands for “I’ll have chicken”, and
P stands for “I’ll have mashed potatoes”
(c)
