A three digit number is created using the digits 4, 5, and 6. Each digit may only be used once. What is the probability that the three digit number will be less than 550?

Question

A three digit number is created using the digits 4, 5, and 6.  Each digit may only be used once.  What is the probability that the three digit number will be less than 550?

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Reiny · Answer

since there are only 6 possibilities, lets list them 456, 465, 546, 564, 645, 654 how many of these are less than 550 ? so ....