Problema Solution

Determine how many four-character codes can be formed if the first character is a nonzero digit, the second character is an odd digit, the third character is any digit, and the last character is a letter of the alphabet, and repetition of digits is allowed.

(A digit is 0, 1, 2,3,4,5,6,8, or 9.)

Answer provided by our tutors

since ist character is a non zero 

hence no of ways it can be used  8

no of ways to write second = 4 ways

 no of ways of third  = 10

 no of ways of foruth = 26

hence total number of ways  = 8 * 4* 10 *26

  = 8320 ways