Problem

Evaluate 9C2

Answer

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Answer

So, the combination of 9 items taken 2 at a time is 36.

Steps

Step 1 :The problem is asking for the combination of 9 items taken 2 at a time.

Step 2 :The formula for combination is given by: C(n,r)=n!r!(nr)! where n is the total number of items, r is the number of items to choose, and ! denotes factorial. In this case, n=9 and r=2.

Step 3 :Substituting the values into the formula, we get C(9,2)=9!2!(92)!

Step 4 :Solving the above expression, we get the combination as 36.

Step 5 :So, the combination of 9 items taken 2 at a time is 36.

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