+42 A palindrome is a number which reads the same forward as backward. How many five-digit palindromes can be made from the digits 1, 2, and 9? (Each digit may be used more than once.)
Also, my brother nerdowizard4578's account. Yeah. He can't sign in. It says unknown username.
+2094 Let's list the possibilities...
92129
91219
29192
21912
12921
19291
99999
11111
22222
11211
22122
99199
99299
22922
11911
So a total of 15 possibilities.
+12 A five-digit palindrome would be of the form ABCBA, where A, B, and C are digits (not necessarily distinct) from 0 to 9 (with A from 1 to 9). We have three possibilities for each of A, B, and C which gives us 3^3 possible 27 palindromes.
+12 A five-digit palindrome would be of the form ABCBA, where A, B, and C are digits (not necessarily distinct) from 0 to 9 (with A from 1 to 9). We have three possibilities for each of A, B, and C which gives us 3^3 possible 27 palindromes.
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