Question

In how many ways can a group of 12 choose a committe of 9

Answer 1

Step-by-step explanation:

my above interpretation is that it is asking for a Combination without repetition or $\frac{(n+r-1)!}{r!(n-1)!}$ which gives you the amount of combinations without repetition (as you cannot pick the same student twice.) Now my teacher argues that the answer the book provides is correct. The books answer simply says to use $^{n}C_{r}$ or $\frac{n!}{r!(n-r)!}$.

The book states 3. 495 is the answer.