+0  
 
0
395
1
avatar+606 

The inhabitants of the island of Jumble use the standard Roman alphabet (26 letters, A through Z). Each word in their language is 3 letters, and for some reason, they insist that all words contain the letter A at least once. How many 3-letter words are possible?

 Apr 22, 2018
 #1
avatar+98005 
+1

The A can appear in any one of 3 positions when it is used once

And there are 25 * 25  posiibilities  for the other two positions

So..... C( 3, 1) * 25^2    = 1875      

 

When the word has 2 A's....they can appear in any two of the three positions

And the the other position can be filled in 25 ways

So  C(3,2) * 25  =  75    

 

And  only one word has three A's  

 

So...the total possible words  =   1875  + 75  + 1  =    1951

 

 

cool cool cool

 Apr 22, 2018

43 Online Users

avatar
avatar
avatar
avatar
avatar
avatar
avatar
avatar
avatar