A is the sum of all even 3-digit numbers in which all the three digits are equal. B is the sum of all odd three digit numbers in which all the digits are equal. Then find the value of B/A JAPAMT - 20151 1 1 1 1 1 up to 20 terms. [AMTI-2013]
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The numbers range from 100 to 999, or 900 numbers. Exactly half of them are even, or 450.
The leftmost digit must range from 1 to 9, for an average value of 5. The second ranges from 0 to 10, for an average value of 4.5, and the last must be one of {0,2,4,6,8}, for an average of 4. It's important to note that in the 450 even numbers, all the allowable digits in each position are used the same number of times.
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