+0  
 
0
709
3
avatar

Consider the set

\(S=\{1,2,3,4,5,6,7,8,9,12,13,14,15,16,17,18,19,23,24,\ldots,123456789\},\)which consists of all positive integers whose digits strictly increase from left to right. This set is finite. What is the median of the set?

 Jul 22, 2018
 #1
avatar
0

I will take a crack at this one!.

 

If you look carefully, you should notice that ALL terms beyond 89 cancel out leaving you with the following 45 terms:

(1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 13, 14, 15, 16, 17, 18, 19, 23, 24, 25, 26, 27, 28, 29, 34, 35, 36, 37, 38, 39, 45, 46, 47, 48, 49, 56, 57, 58, 59, 67, 68, 69, 78, 79, 89)

Therefore, the median of the set is 28.

 Jul 22, 2018
 #3
avatar
0

This is incorrect, those terms do not cancel out.

Guest Jul 26, 2018
 #2
avatar
0

Thanks!

 Jul 23, 2018

0 Online Users