Question
how many positive 4-digit numbers are there with an even digit in the hundreds position and an odd digit in the tens position?
a. 10,000
b. 5,040
c. 2,500
d. 2,250
a. 10,000
b. 5,040
c. 2,500
d. 2,250
Answers
Steve
1st digit has 9 choices
2nd has 5
3rd has 5
4th has 10
so, ...
2nd has 5
3rd has 5
4th has 10
so, ...