You can put this solution on YOUR website! For a three-digit number to be divisible by six, the sum of the digits must be divisible by both 2 and 3.
As you know, all even numbers (ending in 0, 2, 4, 6, or 8) are divisible by 2 so this number will be divisible by 2 no matter what the tens digit is going to be.
To make it also divisible by 3, the tens digit has to be 1 so that the sum of the three digite (2+1+6=9) is divisble by 3.
Answer: The tens digit must be 1 to make the number = 216
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