Which of the following numbers is divisible by 18?

2,358Correct answerYour answer3,465Correct answerYour answer4,326Correct answerYour answer7,142Correct answerYour answer

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CorrectNot quiteAnswer A

Correct answer: A

Divisible by 18 means divisible by both 2 and 9.
2,358 is even and its digit sum is 18, a multiple of 9 — it passes both.
3,465 has digit sum 18 but is odd; 4,326 (digit sum 15) and 7,142 (digit sum 14) fail the test for 9.

Worth noting

4,326 is divisible by 6 (by 2 and 3) but not by 18, which needs 9, not just 3.

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Explanation