Which number is divisible by 18? A. 128646 B. 286531 C. 298650 D. 219751
Hint: In the above question we will use the concept of divisibility rule for 18: if a number is divisible by both 2 and 9, then the number is exactly divisible by 18. For divisibility by 2 the last digit of a number ends with 0, 2, 4, 6, 8. For divisibility by 9 the sum of the digits of the number is divisible by 9.
Complete Step-by-Step solution: Now, in the above question we will check the option one by one as follows: A.128646 Here, the last digit ends with 6, so it is divisible by 2. The sum of digits = 27 is divible by 9. Hence, 128646 is divisible by 18.
B. 286531 Here, the last digit ends with 1, so it is not divisible by 2. Hence, it is also not divible by 18.
C. 298650 Here, the last digit ends with 0, so it is divisible by 2. The sum of digit = 30 is not divisible by 9. Hence, 298650 is not divisible by 18.
D. 219751 Here, the last digit ends with 1, so it is not divisible by 2. Hence, it is also not divisible by 18. Therefore, the correct option of the above question is option A.
Note: Just remember the divisibility rule as it will help you a lot in these types of questions. Some important divisibility rules are for 3, 9 and 11 that you must have to know.