Brain Game: Out of the Ordinal


Cardinal numbers are counting numbers; 1, 2, 3, and so on. Ordinal numbers, on the other hand, represent an order; 1st, 2nd, 3rd, etc. With this in mind, here's today's Brain Game. And a word of caution: if you answer too quickly, you'll probably answer incorrectly! Good luck:

Counting all ordinal numbers from 1st to 100th, how many of them end with the suffix "th"?

Here is the SOLUTION.


73 of them.

The unusual total is the result of the extra "th" entries 11th, 12th, and 13th.

4th through 20th = 17
24th through 30th = 7
34th through 40th = 7
44th through 50th = 7
54th through 60th = 7
64th through 70th = 7
74th through 80th = 7
84th through 90th = 7
94th through 100th = 7