Problem:
A palindrome is a whole number that reads the same forwards as 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?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
In each hour from through , there are six such times. From to , for example, these times are .
From to , there is one such time in each hour: , and . Thus there are a total of such times.
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions