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How many 3 digit palindrome numbers can be formed by using digits 1, 2, 3, 4, 5 and 6?
Can you tell me how many 3 digit palindrome numbers can be formed by using digits 1, 2, 3, 4, 5 and 6?
Sure! There are two cases for forming 3 digit palindromes: one with a repeating digit in the middle and one without. In the first case, there are 6 options for the repeating digit and 5 options for the non-repeating digit. In the second case, there are 6 options for the first digit and 5 options for the third digit. Therefore, the total number of 3 digit palindrome numbers that can be formed using digits 1, 2, 3, 4, 5 and 6 is 6*5 + 6*5 = 60.