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Two Digit Pattern Matching

Pro Problems > Math > Number and Quantity > Number Theory > Digits

Two Digit Pattern Matching

How many two-digit numbers are there such that the digits match at least one of the following patterns:

The digits are both multiples of three.
Neither of the digits are multiples of two.
The digits add to 8.
The digits are perfect squares.

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Problem by Mr. Twitchell

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