Answer:
6,435
Step-by-step explanation:
To find the number of ways the teacher can select the students, we can use the combination formula.
[tex]_{n}C_{k}=\dfrac{n!}{k!(n-k)!}[/tex]
n = 15
k = 7
Now let's plug it in.
[tex]_{n}C_{k}=\dfrac{n!}{k!(n-k)!}[/tex]
[tex]_{15}C_{7}=\dfrac{15!}{7!(15-7)!}[/tex]
[tex]_{15}C_{7}=\dfrac{15!}{7!8!}[/tex]
[tex]_{15}C_{7}=6,435[/tex]
So there are 6,435 ways that the teacher can select the students.