Which is a counterexample to the following conjecture?

If a number is divisible by 2, it must also be divisible by 4.

A.
16

B.
22

C.
8

D.
24

1 answer

The conjecture states: "If a number is divisible by 2, it must also be divisible by 4."

To find a counterexample, we need to identify a number that is divisible by 2, but not divisible by 4.

Let's evaluate the options:

A. 16
- 16 is divisible by 2 (16 ÷ 2 = 8)
- 16 is also divisible by 4 (16 ÷ 4 = 4)
- This is not a counterexample.

B. 22
- 22 is divisible by 2 (22 ÷ 2 = 11)
- 22 is not divisible by 4 (22 ÷ 4 = 5.5)
- This is a counterexample.

C. 8
- 8 is divisible by 2 (8 ÷ 2 = 4)
- 8 is also divisible by 4 (8 ÷ 4 = 2)
- This is not a counterexample.

D. 24
- 24 is divisible by 2 (24 ÷ 2 = 12)
- 24 is also divisible by 4 (24 ÷ 4 = 6)
- This is not a counterexample.

The counterexample to the conjecture is:

B. 22