The positive three-digit integer N has a ones digit of 0. What is the probability that N is divisible by 4? Express your answer as a common fraction.
An integer is divisible by 4 if and only if a number formed from the last two digits is divisible by 4. If the units digit is 0, all the numbers with even tens digits are divisible by 4 (00, 20, 40, 60, 80), and all the numbers with odd tens digits are not (10, 30, 50, 70, 90). Since there are the same number of even digits as odd digits, there is a probability that is divisible by 4.
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