Answer:
![P(X\leq 8)= 1- P(X>8) = 1-P(X\geq 9)= 1-[P(X=9)+P(X=10)]](https://tex.z-dn.net/?f=P%28X%5Cleq%208%29%3D%201-%20P%28X%3E8%29%20%3D%201-P%28X%5Cgeq%209%29%3D%201-%5BP%28X%3D9%29%2BP%28X%3D10%29%5D)
And we can find the individual probabilities like this:
And replacing we got:
![P(X\leq 8)=1-[10(0.8)^1 (1-0.8)^{1} + (0.8)^{10}]](https://tex.z-dn.net/?f=P%28X%5Cleq%208%29%3D1-%5B10%280.8%29%5E1%20%281-0.8%29%5E%7B1%7D%20%2B%20%280.8%29%5E%7B10%7D%5D)
Step-by-step explanation:
Previous concepts
A Bernoulli trial is "a random experiment with exactly two possible outcomes, "success" and "failure", in which the probability of success is the same every time the experiment is conducted". And this experiment is a particular case of the binomial experiment.
The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".
The probability mass function for the Binomial distribution is given as:
Where (nCx) means combinatory and it's given by this formula:
The complement rule is a theorem that provides a connection between the probability of an event and the probability of the complement of the event. Lat A the event of interest and A' the complement. The rule is defined by:
Solution to the problem
For this case we want this probability:

And for this case we can use the comlement rule and we got:
![P(X\leq 8)= 1- P(X>8) = 1-P(X\geq 9)= 1-[P(X=9)+P(X=10)]](https://tex.z-dn.net/?f=P%28X%5Cleq%208%29%3D%201-%20P%28X%3E8%29%20%3D%201-P%28X%5Cgeq%209%29%3D%201-%5BP%28X%3D9%29%2BP%28X%3D10%29%5D)
And we can find the individual probabilities like this:
And replacing we got:
![P(X\leq 8)=1-[10(0.8)^9 (1-0.8)^{1} + (0.8)^{10}]](https://tex.z-dn.net/?f=P%28X%5Cleq%208%29%3D1-%5B10%280.8%29%5E9%20%281-0.8%29%5E%7B1%7D%20%2B%20%280.8%29%5E%7B10%7D%5D)
Answer:
Gerald will need to conduct fewer trials because experimental and theoretical results in experiments with small
numbers of possible outcomes are the same.
Answer:

Step-by-step explanation:

Answer:
The third number is 180.
Step-by-step explanation:
Let the third number be 9x where x is an integer.
48 = 2*2*2*2*3
264 = 2*2*2*3*11
9x = 3*3*x
2*2*2*2*3*3*11*x = 7920y where y is an integer
1584x = 7920y
so x = 7920y / 1584= 5y.
Now the GCD is 12 so x must have 4 as one of its factors.
Also x is a multiple of 5 so it could be 20 then y would be 4.
If x = 20 then the third number is 9*20 = 180.
This checks out OK.
Answer:
a) The confidence interval is
.
Step-by-step explanation:
We have to calculate a confidence interval (CI) of a difference of proportions.
For the existing procedure, the proportion is:

For the new procedure, the proportion is:

To calculate the CI, we need to estimate the standard deviation

For a 90% CI, the z-value is 1.64.
Then, the CI is:
