Jennifer believes that any integer that has 3 as its ones-digit is divisible but 3. What is the BEST serves as a counterexample to prove Jennifer's conjecture is false?

Question

directrix · Answer

Are we selecting from options? Or, are we to come up with any counterexample?
@jewlzme17

jewlzme17 · Answer

come up with any counterexample @Directrix

directrix · Answer

Name a number that has 3 as its ones-digit and something else for its tens digit. Post it and we'll check it.

jewlzme17 · Answer

so like 23? I don't really get this because we learned it at the beginning of my school year and we are reviewing for finals

directrix · Answer

Let's check 23.

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Claim: any integer that has 3 as its ones-digit is divisible by 3.

Counterexample: 23 has 3 as its ones-digit but 23 is NOT divisible by 3 because 23/3 = 7 2/3 which is NOT an integer.

Therfore, the claim is false.

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PS In this context, to say that 3 divides a number means that the quotient has to be an integer.

jewlzme17 · Answer

ohh okay I see!! thank you!

directrix · Answer

Great. That's good news.