1988 AJHSME Problems/Problem 25
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Problem
A palindrome is a whole number that reads the same forwards and backwards. If one neglects the colon, certain times displayed on a digital watch are palindromes. Three examples are: , , and . How many times during a -hour period will be palindromes?
Solution
From to , the times will be of the form . There are choices for and choices for , so there are times in this period.
From to , the minutes are already determined, so there are only times in this case.
In total, there are palindromic times.
See Also
1988 AJHSME (Problems • Answer Key • Resources) | ||
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