Using The Digits One Through Nine How Many "Two Digit" Numbers Can Be Found Which Do Not Contain A Four Or Five?

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Oddman answered
There are 8 digits, not counting 4 or 5. Thus, there are 8^2 = 64 numbers not counting ones with 4 or 5. The smallest is 00, the largest is 99. (8 of them are smaller than 10.)

00, 01, 02, 03, 06, 07, 08, 09,
10, 11, 12, 13, 16, 17, 18, 19,
20, 21, 22, 23, 26, 27, 28, 29,
30, 31, 32, 33, 36, 37, 38, 39,
60, 61, 62, 63, 66, 67, 68, 69,
70, 71, 72, 73, 76, 77, 78, 79,
80, 81, 82, 83, 86, 87, 88, 89,
90, 91, 92, 93, 96, 97, 98, 99

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