alleryStart learning →The digits of a number add up to 21. The number must be divisible by what?
Aneither 3 nor 9
B3 but not 9
C9 but not 3
Dboth 3 and 9
Answer & Solution
Correct answer: B. 3 but not 9
21 is a multiple of 3 but not of 9, so the number is divisible by 3 only.
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