SOLUTION: In how many 4 digit integers does the digit 5 appear once and only once and as the largest digit? Answers: A. 425 B. 225 C. 400 D. 600

 

Hi,

In how many 4 digit integers does the digit 5 appear once and only once and as the largest digit?

Note: there are 5 digits < 5 , however, 0 cannot be in the first position  

5 in 1st position:  ways

5 in 2nd position:  ways

5 in 3rd position:  ways

5 in 4th position:  ways