Question

Write the following statements as mathematical implications:

(c) "it is necessary that positive numbers are > 7.

(d) to show a number is +, it is sufficient to show it is >10.

Answer 1

Lets say that

p: x is a positive numbre

q: x > 7

r : x > 10

Then,

(C) if 'p', then 'q' (if a number is positive, then it is >7)

p》q

(D) if 'r', then 'p' (if a number is >10 then it is positive)

r》p