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When a customer buys a familysized meal at certain restaurant, they get to choose 3 side dishes from 9 options. Suppose a customer is going to choose 3 different side dishes.
How many groups of 3 different side dishes are possible?

When a customer buys a familysized meal at certain restaurant, they get to choose 33 side dishes from 99 options. Suppose a customer is going to choose 33 different side dishes.\newlineHow many groups of 33 different side dishes are possible?

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Q. When a customer buys a familysized meal at certain restaurant, they get to choose 33 side dishes from 99 options. Suppose a customer is going to choose 33 different side dishes.\newlineHow many groups of 33 different side dishes are possible?
  1. Identify problem type: Identify the problem type.\newlineWe need to find the number of combinations of 33 side dishes that can be chosen from 99 options. This is a combination problem because the order in which the side dishes are chosen does not matter.
  2. Use combination formula: Use the combination formula.\newlineThe number of ways to choose 33 items from 99 is given by the combination formula: C(n,k)=n!k!(nk)!C(n, k) = \frac{n!}{k!(n-k)!}, where nn is the total number of items to choose from, kk is the number of items to choose, "!!" denotes factorial, and C(n,k)C(n, k) is the number of combinations.
  3. Calculate number of combinations: Calculate the number of combinations.\newlineUsing the combination formula with n=9n=9 and k=3k=3, we get:\newlineC(9,3)=9!3!(93)!=9!3!6!=9×8×73×2×1=5046=84C(9, 3) = \frac{9!}{3!(9-3)!} = \frac{9!}{3!6!} = \frac{9\times8\times7}{3\times2\times1} = \frac{504}{6} = 84.

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