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Finite Math Examples
C810
Step 1
Evaluate C810 using the formula Crn=n!(n-r)!r!.
10!(10-8)!8!
Step 2
Subtract 8 from 10.
10!(2)!8!
Step 3
Step 3.1
Rewrite 10! as 10⋅9⋅8!.
10⋅9⋅8!(2)!8!
Step 3.2
Cancel the common factor of 8!.
Step 3.2.1
Cancel the common factor.
10⋅9⋅8!(2)!8!
Step 3.2.2
Rewrite the expression.
10⋅9(2)!
10⋅9(2)!
Step 3.3
Multiply 10 by 9.
90(2)!
Step 3.4
Simplify the denominator.
Step 3.4.1
Expand (2)! to 2⋅1.
902⋅1
Step 3.4.2
Multiply 2 by 1.
902
902
Step 3.5
Divide 90 by 2.
45
45