Karim has 23 candies. He eats candies and divides the remaining candies equally among his three children so that each child gets an integer number of candies. Which of the following is not a possible value of ?
Solution
After Karim eats candies, he has candies remaining. Since he divides these candies equally among his three children, the integer must be a multiple of 3. If , we obtain , each of which is a multiple of 3. If , we obtain , which is not a multiple of 3. Therefore, cannot equal 9.
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