Multiple choice If 18a71 is divisible by 3, where 'a' is a digit then the value of 'a' is 0 1 2 None of these Reveal answer Fill a bubble to check yourself B Correct answer Explanation A number is divisible by 3 if the sum of its digits is divisible by 3. Sum = 1+8+a+7+1 = 17+a. For 17+a to be divisible by 3, a must be 1 (18) or 4 (21) or 7 (24). Given options, 1 is correct.