WMC 2018 Senior Problem 5

Level 1

Suppose all 120 possible arrangements of the letters S, E, A, M and C are placed in alphabetical order. What is the 100 t h {100}^{th} “word”?

SEAMC SECAM SEACM SAEMC SAECM

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Julian Yu
Oct 10, 2018

The letters, in alphabetical order, are A, C, E, M, S, and there are 4 ! = 24 4!=24 words beginning with each letter.

Therefore, the first 96 96 words in the list are all the words beginning with A , C , E , M A,C,E,M which means that the 100th word is the fourth word beginning with S S . Now we can list them in order: SACEM, SACME, SAECM, SAEMC. Therefore, the answer is SAEMC.

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...