The formula for N choose K is given as:
C(n, k)= ![\frac{n!}{[k!(n-k)!] }](https://tex.z-dn.net/?f=%20%5Cfrac%7Bn%21%7D%7B%5Bk%21%28n-k%29%21%5D%20%20%7D)
Where,
n is the total numbers.
k is the number of the selected item.
Options C is correct.
Alex bought all the string needed for $125.
It costs $18 for the remaining materials to make each puppet.
So if we closely observe then we see that here $125 is the fixed cost because its not going to change with number of puppets.
And the variable cost is $18.
In this case we can model a Total cost function C(x) for for x number of puppets as below

The total cost to make 50 puppets=$1025
Answer:
28
Step-by-step explanation:
First, find the ratio between the triangles. To do this, divide any side of the big triangle by corresponding side in the small triangle. I chose 35. So, 35/10 = 3.5. 3.5 is the ratio between the triangles. Multiply 3.5 by 8 to get 28, the length of the missing side. :)