1.Suppose we are given logic statements p, q, and r.

a. If p → q and p → r, may we conclude that q → r? Answer yes or no and give a reason why.

b. What is the converse of the following: not p → not q

c. What is the contrapositive of r → q?

d. The statements p → q and q → r are given. If we know q is true, is p necessarily true? Explain.

1 answer

(a) No
If it rains, I'll eat chicken.
If it rains, I'll go outside.
No way to conclude that eating chicken means going outside.

(b) Come on. You know that the converse of p→q id q→p. So, ...

(c) ~q → ~r

(d) Nope. I'm sure you can come up with an example. (Use what you know about converses.)