The correct answer is 10.
In order to evaluate any composite function, you need to first put the value in for the inside function. In this case f(x) is on the inside along with the number 3. So, we input 3 in for x in f(x).
f(x) = 2x + 1
f(3) = 2(3) + 1
f(3) = 6 + 1
f(3) = 7
Now that we have the value of f(3), we can stick the answer in for the outside function, which is g(x).
g(x) = (3x - 1)/2
g(7) = (3(7) - 1)/ 2
g(7) = (21 - 1)/2
g(7) = 20/2
g(f(3)) = 10
The number of possible combinations is given by
... C(18, 3) = 18!/(3!(18-3)!) = 18·17·16/(3·2·1) = 816 . . . . possible combinations
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There are 18 ways to choose the first one; 17 ways to choose the second one, and 16 ways to choose the 3rd one. The same 3 students can be chosen in any of 3! = 6 different orders, so the product 18·17·16 must be divided by 6 to get the number of possible combinations in which order doesn't matter.
No no no no no no no no no jk its c your welcome
