Suppose a math class has 24 students In how many ways can fo

Suppose a math class has 24 students. In how many ways can four students be selected to take part in a survey? In how many ways can four students be selected to do 4 different mathematical problems on the board? Use commas where appropriate.

Solution

Out of 24 students , no. of ways 4 students can be selected = 24C4 = 24!/4!*20!

= 10626

ways can four students be selected to do 4 different mathematical problems on the board

= 24*23*22*21*20

= 5100480