Answer:
So then the minimum sample to ensure the condition given is n= 38
Step-by-step explanation:
Notation
represent the sample mean for the sample
population mean (variable of interest)
represent the population standard deviation
n represent the sample size
ME = 4 the margin of error desired
Solution to the problem
When we create a confidence interval for the mean the margin of error is given by this formula:
(a)
And on this case we have that ME =4 and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
The critical value for 96% of confidence interval now can be founded using the normal distribution. The significance is . And in excel we can use this formula to find it:"=-NORM.INV(0.02;0;1)", and we got , replacing into formula (b) we got:
So then the minimum sample to ensure the condition given is n= 38
Answer:
Probability of having at least 4 Girls
= 0.6875
Step-by-step explanation:
Probability of having at least 4 Girls is 1-probability of having exactly 3 girls
Total number of children= 5 = N
Probability of having a girl p = 0.5
Probability of not having a girl q= 0.5
X= 3
Probability of at least 4 girls is given by
Probability= NCX(p)^x(q)^(N-x)
Probability = 5C3(0.5)^3(0.5)^(5-3)
Probability = 5C3(0.5)^3(0.5)^2
Probability= 5!/3!2!(0.5)^3(0.5)^2
Probability= 10(0.125)(0.25)
Probability= 0.3125
Probability of having at least 4 Girls
= 1- 0.3125
= 0.6875
The answer would be 9, because you have the 3 edges along the rectangles, and then 3 edges each for the triangles. So 3 + 3 + 3 = 9. I hope this helps!