Problem 317
Classify as true or false, and if false, give a counterexample.
a. If 3 │ n, then 9 │ n.
b. If 10 │ n , then 5 │ n.
c. If 2 │ n and 4 │ n , then 8 │ n.
Solution
a. False, 3 divides 12 but 9 does not.
b. True, 5 is factor of 10
c. False, 2 and 4 divide 28 but 8 does not divide 28.