Finite Math Examples
x<3x<3 , n=3n=3 , p=0.4p=0.4
Step 1
Subtract 0.40.4 from 11.
0.60.6
Step 2
When the value of the number of successes xx is given as an interval, then the probability of xx is the sum of the probabilities of all possible xx values between 00 and nn. In this case, p(x<3)=P(x=0)+P(x=1)+P(x=2)p(x<3)=P(x=0)+P(x=1)+P(x=2).
p(x<3)=P(x=0)+P(x=1)+P(x=2)p(x<3)=P(x=0)+P(x=1)+P(x=2)
Step 3
Step 3.1
Use the formula for the probability of a binomial distribution to solve the problem.
p(x)=C03⋅px⋅qn-xp(x)=3C0⋅px⋅qn−x
Step 3.2
Find the value of C033C0.
Step 3.2.1
Find the number of possible unordered combinations when rr items are selected from nn available items.
C03=Crn=n!(r)!(n-r)!3C0=nCr=n!(r)!(n−r)!
Step 3.2.2
Fill in the known values.
(3)!(0)!(3-0)!(3)!(0)!(3−0)!
Step 3.2.3
Simplify.
Step 3.2.3.1
Simplify the numerator.
Step 3.2.3.1.1
Expand (3)!(3)! to 3⋅2⋅13⋅2⋅1.
3⋅2⋅1(0)!(3-0)!3⋅2⋅1(0)!(3−0)!
Step 3.2.3.1.2
Multiply 3⋅2⋅13⋅2⋅1.
Step 3.2.3.1.2.1
Multiply 33 by 22.
6⋅1(0)!(3-0)!6⋅1(0)!(3−0)!
Step 3.2.3.1.2.2
Multiply 66 by 11.
6(0)!(3-0)!6(0)!(3−0)!
6(0)!(3-0)!6(0)!(3−0)!
6(0)!(3-0)!6(0)!(3−0)!
Step 3.2.3.2
Simplify the denominator.
Step 3.2.3.2.1
Expand (0)!(0)! to 11.
61(3-0)!61(3−0)!
Step 3.2.3.2.2
Subtract 00 from 33.
61(3)!61(3)!
Step 3.2.3.2.3
Expand (3)!(3)! to 3⋅2⋅13⋅2⋅1.
61(3⋅2⋅1)61(3⋅2⋅1)
Step 3.2.3.2.4
Multiply 3⋅2⋅13⋅2⋅1.
Step 3.2.3.2.4.1
Multiply 33 by 22.
61(6⋅1)61(6⋅1)
Step 3.2.3.2.4.2
Multiply 66 by 11.
61⋅661⋅6
61⋅661⋅6
Step 3.2.3.2.5
Multiply 66 by 11.
6666
6666
Step 3.2.3.3
Divide 66 by 66.
11
11
11
Step 3.3
Fill the known values into the equation.
1⋅(0.4)0⋅(1-0.4)3-01⋅(0.4)0⋅(1−0.4)3−0
Step 3.4
Simplify the result.
Step 3.4.1
Multiply (0.4)0(0.4)0 by 11.
(0.4)0⋅(1-0.4)3-0(0.4)0⋅(1−0.4)3−0
Step 3.4.2
Anything raised to 00 is 11.
1⋅(1-0.4)3-01⋅(1−0.4)3−0
Step 3.4.3
Multiply (1-0.4)3-0(1−0.4)3−0 by 11.
(1-0.4)3-0(1−0.4)3−0
Step 3.4.4
Subtract 0.40.4 from 11.
0.63-00.63−0
Step 3.4.5
Subtract 00 from 33.
0.630.63
Step 3.4.6
Raise 0.60.6 to the power of 33.
0.2160.216
0.2160.216
0.2160.216
Step 4
Step 4.1
Use the formula for the probability of a binomial distribution to solve the problem.
p(x)=C13⋅px⋅qn-xp(x)=3C1⋅px⋅qn−x
Step 4.2
Find the value of C133C1.
Step 4.2.1
Find the number of possible unordered combinations when rr items are selected from nn available items.
C13=Crn=n!(r)!(n-r)!3C1=nCr=n!(r)!(n−r)!
Step 4.2.2
Fill in the known values.
(3)!(1)!(3-1)!(3)!(1)!(3−1)!
Step 4.2.3
Simplify.
Step 4.2.3.1
Subtract 11 from 33.
(3)!(1)!(2)!(3)!(1)!(2)!
Step 4.2.3.2
Rewrite (3)!(3)! as 3⋅2!3⋅2!.
3⋅2!(1)!(2)!3⋅2!(1)!(2)!
Step 4.2.3.3
Cancel the common factor of 2!2!.
Step 4.2.3.3.1
Cancel the common factor.
3⋅2!(1)!(2)!
Step 4.2.3.3.2
Rewrite the expression.
3(1)!
3(1)!
Step 4.2.3.4
Expand (1)! to 1.
31
Step 4.2.3.5
Divide 3 by 1.
3
3
3
Step 4.3
Fill the known values into the equation.
3⋅(0.4)⋅(1-0.4)3-1
Step 4.4
Simplify the result.
Step 4.4.1
Evaluate the exponent.
3⋅0.4⋅(1-0.4)3-1
Step 4.4.2
Multiply 3 by 0.4.
1.2⋅(1-0.4)3-1
Step 4.4.3
Subtract 0.4 from 1.
1.2⋅0.63-1
Step 4.4.4
Subtract 1 from 3.
1.2⋅0.62
Step 4.4.5
Raise 0.6 to the power of 2.
1.2⋅0.36
Step 4.4.6
Multiply 1.2 by 0.36.
0.432
0.432
0.432
Step 5
Step 5.1
Use the formula for the probability of a binomial distribution to solve the problem.
p(x)=C23⋅px⋅qn-x
Step 5.2
Find the value of C23.
Step 5.2.1
Find the number of possible unordered combinations when r items are selected from n available items.
C23=Crn=n!(r)!(n-r)!
Step 5.2.2
Fill in the known values.
(3)!(2)!(3-2)!
Step 5.2.3
Simplify.
Step 5.2.3.1
Subtract 2 from 3.
(3)!(2)!(1)!
Step 5.2.3.2
Rewrite (3)! as 3⋅2!.
3⋅2!(2)!(1)!
Step 5.2.3.3
Cancel the common factor of 2!.
Step 5.2.3.3.1
Cancel the common factor.
3⋅2!(2)!(1)!
Step 5.2.3.3.2
Rewrite the expression.
3(1)!
3(1)!
Step 5.2.3.4
Expand (1)! to 1.
31
Step 5.2.3.5
Divide 3 by 1.
3
3
3
Step 5.3
Fill the known values into the equation.
3⋅(0.4)2⋅(1-0.4)3-2
Step 5.4
Simplify the result.
Step 5.4.1
Raise 0.4 to the power of 2.
3⋅0.16⋅(1-0.4)3-2
Step 5.4.2
Multiply 3 by 0.16.
0.48⋅(1-0.4)3-2
Step 5.4.3
Subtract 0.4 from 1.
0.48⋅0.63-2
Step 5.4.4
Subtract 2 from 3.
0.48⋅0.61
Step 5.4.5
Evaluate the exponent.
0.48⋅0.6
Step 5.4.6
Multiply 0.48 by 0.6.
0.288
0.288
0.288
Step 6
Step 6.1
Add 0.216 and 0.432.
p(x<3)=0.648+0.288
Step 6.2
Add 0.648 and 0.288.
p(x<3)=0.936
p(x<3)=0.936