math class 13 girls, 11 boys

[xc630]

Hello, I would like some help with this problem. In a math class with 13 girls and 11 boys, the teacher randomly selects 4 students to put hw problems on the board. What is the probability that all are girls?

I think I would do the number of possibilites with 13 girls over the toal number of possibilities but how would I do this?

 

[pka]

I think I would do the number of possibilites with 13 girls over the toal number of possibilities but how would I do this?

That is the correct way to do this problem.

 

[xc630]

how do I find the number of possibilities for girls and the total number of possibilities?

 

[Denis]

1st selection: 13 out of 24; 2nd selection: 12 out of 23; finish it