Answer:
(i) no, remainder is 6
(ii) no, remainder is 6
(iii) yes
Step-by-step explanation:
A number is divisible by 9 when the sum of its digits is divisible by 9. (The process of computing the sum of digits is called "casting out 9s".) You can basically treat any 9 as though it were 0.
(i) 3+9+4+6+8+3 = 33, 3+3 = 6. The remainder from division by 9 is 6. 9 is not a factor.
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(ii) 1 + 8 + 7 + 2 + 5 + 4 + 6 = 9 + 9 + 9 + 6 = 33, 3+3 = 6. The remainder from division by 9 is 6. 9 is not a factor.
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(iii) 5 + 1 + 7 + 2 + 3 + 5 + 4 = 6 + 9 + 3 + 9 = 27 = 3×9. This is divisible by 9, so the number is divisible by 9. 9 is a factor.
