Answer: 0.476
Step-by-step explanation:
Let A = Event of choosing an even number ball.
B = Event of choosing an 8 .
Given, A lottery game has balls numbered 1 through 21.
Sample space: S= {1,2,3,4,5,6,7,8,...., 21}
n(S) = 21
Then, A= {2,4,6,8, 10,...(20)}
i.e. n(A)= 10
B= {8}
n(B) = 1
A∪B = {2,4,6,8, 10,...(20)} = A
n(A∪B)=10
Now, the probability of selecting an even numbered ball or an 8 is


Hence, the required probability =0.476
If you think about it, the question is asking us to find the greatest common factor, or GCF, of the two numbers, 24 and 18.
First, find all of the factors of 24.
The factors are: 1, 2, 3, 4, 6, 8, 12, 24
Next, find the factors of 18.
The factors are: 1, 2, 3, 6, 9, 18
List out all of the factors that both of the numbers have.
The factors are: 1, 2, 3, 6
Whichever is the greatest of these numbers is the GCF.
The GCF is 6, so the greatest number of groups he can make and still be able to win is 6.
Hope this helps!
Answer:
Step-by-step explanation:
For the sample, n = 12
Mean, x = (158.2 + 162.8 + 161.5 + 161.2 + 166.5 + 160.1 + 158.4 + 175.6 + 159.9 + 168.8 + 161.9 + 163.7)/12 = 163.22
Variance, s² = (summation(x - mean)²/n
Summation(x - mean)² = (158.2 - 163.22)^2 + (162.8 - 163.22)^2 + (161.5 - 163.22)^2 + (161.2 - 163.22)^2+ (166.5 - 163.22)^2 + (160.1 - 163.22)^2 + (158.4 - 163.22)^2 + (175.6 - 163.22)^2 + (159.9 - 163.22)^2 + (168.8 - 163.22)^2 + (161.9 - 163.22)^2 + (163.7 - 163.22)^2 = 273.5368
Variance, s² = 273.5368/12 = 22.79
This is a test for a single variance. We would set up the test hypothesis.
For the null hypothesis,
H0: σ² ≥ 25
For the alternative hypothesis,
H1: σ² < 25
The formula for determining the test statistic,x² is
x² = (n - 1)s²/σ²
Where n - 1 is the degree of freedom, df.
df = 12 - 1 = 11
x² = (11 × 22.79)/25 = 10.0276
For a test of 90% reliability, Confidence level = 0.9
Cl = 1 - alpha(level of significance)
alpha = 1 - 0.9 = 0.1
The critical value from the chi-square distribution table is 17.28. Since 17.28 > 10.0276, we would reject the null hypothesis. Therefore, the filling machine does not need repair because the variance of the process is not more than 25 oz.
It is B. the differences are added together