If a code word is defined to be a sequence of different letters chosen from the 10 letters A, B, C, D, E, F, G, H, I, and J, what is the ratio of the number of 5-letter code words to the number of 4-letter code words? Choose the correct choice from the following choices:
A) 5 to 4
B) 3 to 2
C) 2 to 1
D) 5 to 1
E) 6 to 1
Method #1: Using the permutation formula   # of 5 letter code words:   nPr = n! / (n – r)! = 10! / (10 – 5)! = 10*9*8*7*6   # of 4 letter code words:   nPr = 10! / (10 – 4)! = 10*9*8*7   # of 5 words / # of 4 words = (10*9*8*7*6)/(10*9*8*7)= 
<gadget id="calculator">(10*9*8*7*6)/(10*9*8*7)</gadget>
<output>6</output>
6= 6/1   Answer is 6 to 1.
<result>E</result>
If a code word is defined to be a sequence of different letters chosen from the 10 letters A, B, C, D, E, F, G, H, I, and J, what is the ratio of the number of 5-letter code words to the number of 4-letter code words?