Finite Math Examples
x=1 , n=3 , p=0.2
Step 1
Use the formula for the probability of a binomial distribution to solve the problem.
p(x)=C13⋅px⋅qn-x
Step 2
Step 2.1
Find the number of possible unordered combinations when r items are selected from n available items.
C13=Crn=n!(r)!(n-r)!
Step 2.2
Fill in the known values.
(3)!(1)!(3-1)!
Step 2.3
Simplify.
Step 2.3.1
Subtract 1 from 3.
(3)!(1)!(2)!
Step 2.3.2
Rewrite (3)! as 3⋅2!.
3⋅2!(1)!(2)!
Step 2.3.3
Cancel the common factor of 2!.
Step 2.3.3.1
Cancel the common factor.
3⋅2!(1)!(2)!
Step 2.3.3.2
Rewrite the expression.
3(1)!
3(1)!
Step 2.3.4
Expand (1)! to 1.
31
Step 2.3.5
Divide 3 by 1.
3
3
3
Step 3
Fill the known values into the equation.
3⋅(0.2)⋅(1-0.2)3-1
Step 4
Step 4.1
Evaluate the exponent.
3⋅0.2⋅(1-0.2)3-1
Step 4.2
Multiply 3 by 0.2.
0.6⋅(1-0.2)3-1
Step 4.3
Subtract 0.2 from 1.
0.6⋅0.83-1
Step 4.4
Subtract 1 from 3.
0.6⋅0.82
Step 4.5
Raise 0.8 to the power of 2.
0.6⋅0.64
Step 4.6
Multiply 0.6 by 0.64.
0.384
0.384