<p>If the product of 3 positive integers is even, which of the following must be true?</p>
<p>A) All of the integers are odd
B) All of the integers are even
C) Two of the integers are even and one is odd.
D) At least one of the integers is odd
E) At least one of the integers is even.</p>
<p>Well 1 x 2 x 3 = 6, which is even ... and 1 and 3 are odd numbers so you can obviously eliminate A, B, an C. Yeah, 2 is even but how about if you do 2 x 3 x 4? Multiply that, and you have 24, which is even .... and 3 is odd. So D and E both work ... therefore, there's no 1 "right" answer. Am I wrong? I feel like I wanna shoot myself ...</p>
<p>DONT PLUG IN NUMBERS! its asking for which MUST be true, not which CAN be true.
B can be true - all numbers are even - 2 x 2 x 2 = 8
C can be true - 2 even 1 odd - 2 x 2 x 3 = 12
D and E can be true as you pointed out</p>
<p>you have to find out which rule MUST be true for all positive integers</p>
<p>odd x odd = odd
odd x even = even
even x even = even</p>
<p>^figure out why these rules are true by yourself. dont make up numbers and try them out on your calculator. use your brain. its a conceptual question</p>
<p>E is the answer because you need an even number. If there was no even number it would be all odd, and odd x odd x odd is always odd</p>