Answer:
0.0579 is the probability that mean systolic blood pressure is between 119 and 122 mm Hg for the sample.
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 114.8 mm Hg
Standard Deviation, σ = 13.1 mm Hg
Sample size = 23
We are given that the distribution of systolic blood pressures is a bell shaped distribution that is a normal distribution.
Formula:
Standard error due to sampling:
P(blood pressure is between 119 and 122 mm Hg)
0.0579 is the probability that mean systolic blood pressure is between 119 and 122 mm Hg for the sample.
38.72 divided by 1.1 equals to 35.2.
Hope this Helped! :)
Answer:
5.96% probability that exactly 3 people in the sample are afraid of being alone at night.
Step-by-step explanation:
For each person, there are only two possible outcomes. Either they are afraid of being alone at night, or they are not. The probability of a person being afraid of being alone at night is independent of any other person. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
In which 
is the number of different combinations of x objects from a set of n elements, given by the following formula.
And p is the probability of X happening.
5% of Americans are afraid of being alone in a house at night.
This means that 
If a random sample of 20 Americans is selected, what is the probability that exactly 3 people in the sample are afraid of being alone at night.
This is P(X = 3) when n = 20. So
5.96% probability that exactly 3 people in the sample are afraid of being alone at night.
Answer:
5/6
Step-by-step explanation:
Hope this helped!!!
