If a code word is defined to be a sequence of different letters chosen from the 8 letters A, B, C, D, E, F, G, AND H, what is the ratio of the number of 5-letter code words to the number of 4-letter code words?
Pick.
A) 4 B) 8 C) 5 D) 10 E) 12
Method #1: Using the permutation formula   # of 5 letter code words:   nPr = n! / (n – r)! = 8! / (8 – 5)! = 8*7*6*5*4   # of 4 letter code words:   nPr = 8! / (8 – 4)! = 8*7*6*5   # of 5 words / # of 4 words = (8*7*6*5*4)/(8*7*6*5)= 
<gadget id="calculator">(8*7*6*5*4)/(8*7*6*5)</gadget>
<output>4</output>
4= 4   4
<result>A</result>
If a code word is defined to be a sequence of different letters chosen from the 8 letters A, B, C, D, E, F, G, AND H, what is the ratio of the number of 5-letter code words to the number of 4-letter code words?