If the probability of winning a slot machine is 5% and you are going to play 500 pulls. Using a normal approximation. What’s the probability that you win less than 40? What’s the probability that you win 30?
In: Statistics and Probability
Consider the probability that exactly 95 out of 151 people have not been in a car accident. Assume the probability that a given person has not been in a car accident is 65%.
Approximate the probability using the normal distribution.
In: Statistics and Probability
Scenario 2:
Randy and Samantha are shopping for new cars (one each). Randy expects to pay $15,000 with 1/5 probability and $20,000 with 4/5 probability. Samantha expects to pay $12,000 with 1/4 probability and $20,000 with 3/4 probability. Refer to Scenario 2. Which of the following is true?
A. Randy and Samantha have the same expected expense for the car: $20,000.
B. Randy has a higher expected expense than Samantha for the car.
C. Randy has a lower expected expense than Samantha for the car.
D. Randy and Samantha have the same expected expense for the car, and it is somewhat less than $20,000
E. It is not possible to calculate the expected expense for the car until the true probabilities are known.
In: Economics
An automatic machine in a manufacturing process is operating properly if the lengths of an important subcomponent are normally distributed with a mean of 111 cm and a standard deviation of 5.5 cm.
A. Using Excel, find the probability that one selected subcomponent is longer than 113 cm.
Probability =
B. Using Excel, find the probability that if 3 subcomponents are randomly selected, their mean length exceeds 113 cm.
Probability =
In: Statistics and Probability
What would be the value of the mean for a binomial distribution that 141 trials and a success probability of 0.19?
What would be the value of the mean for a binomial distribution that 186 trials and a success probability of 0.68?
What would be the value of the mean for a binomial distribution that 80 trials and a success probability of 0.49?
What would be the value of the mean for a binoial distribution that 175 trials and a success probability of 0.09?
In: Statistics and Probability
You would like to study the weight of students at your
university. Suppose the average for all university students is 159
with a SD of 27 lbs, and that you take a sample of 31
students from your university.
a) What is the probability that the sample has a
mean of 160 or more lbs?
probability =
b) What is the probability that the sample has a
mean between 164 and 167 lbs?
probability =
In: Statistics and Probability
Suppose the heights of 18-year-old men are approximately normally distributed, with mean 68 inches and standard deviation 5 inches. (a) What is the probability that an 18-year-old man selected at random is between 67 and 69 inches tall? (Round your answer to four decimal places.) (b) If a random sample of twelve 18-year-old men is selected, what is the probability that the mean height x is between 67 and 69 inches? (Round your answer to four decimal places.) (c) Compare your answers to parts (a) and (b). Is the probability in part (b) much higher? Why would you expect this? The probability in part (b) is much higher because the standard deviation is larger for the x distribution. The probability in part (b) is much lower because the standard deviation is smaller for the x distribution. The probability in part (b) is much higher because the mean is larger for the x distribution. The probability in part (b) is much higher because the mean is smaller for the x distribution. The probability in part (b) is much higher because the standard deviation is smaller for the x distribution.
In: Statistics and Probability
Suppose the heights of 18-year-old men are approximately normally distributed, with mean 69 inches and standard deviation 1 inches.
(a) What is the probability that an 18-year-old man selected at
random is between 68 and 70 inches tall? (Round your answer to four
decimal places.)
(b) If a random sample of fifteen 18-year-old men is selected, what
is the probability that the mean height x is between 68
and 70 inches? (Round your answer to four decimal places.)
(c) Compare your answers to parts (a) and (b). Is the probability
in part (b) much higher? Why would you expect this?
The probability in part (b) is much higher because the mean is smaller for the x distribution.
The probability in part (b) is much higher because the standard deviation is larger for the x distribution.
The probability in part (b) is much lower because the standard deviation is smaller for the x distribution.
The probability in part (b) is much higher because the standard deviation is smaller for the x distribution.
The probability in part (b) is much higher because the mean is larger for the x distribution.
In: Statistics and Probability
Suppose the heights of 18-year-old men are approximately normally distributed, with mean 71 inches and standard deviation 5 inches.
(a) What is the probability that an 18-year-old man selected at
random is between 70 and 72 inches tall? (Round your answer to four
decimal places.)
(b) If a random sample of eighteen 18-year-old men is selected,
what is the probability that the mean height x is between
70 and 72 inches? (Round your answer to four decimal places.)
(c) Compare your answers to parts (a) and (b). Is the probability
in part (b) much higher? Why would you expect this?
The probability in part (b) is much higher because the standard deviation is larger for the x distribution.
The probability in part (b) is much higher because the mean is larger for the x distribution.
The probability in part (b) is much higher because the standard deviation is smaller for the x distribution.
The probability in part (b) is much higher because the mean is smaller for the x distribution.
The probability in part (b) is much lower because the standard deviation is smaller for the x distribution.
In: Statistics and Probability
Suppose the heights of 18-year-old men are approximately normally distributed, with mean 71 inches and standard deviation 4 inches.
(a) What is the probability that an 18-year-old man selected at
random is between 70 and 72 inches tall? (Round your answer to four
decimal places.)
(b) If a random sample of twenty 18-year-old men is selected, what
is the probability that the mean height x is between 70
and 72 inches? (Round your answer to four decimal places.)
(c) Compare your answers to parts (a) and (b). Is the probability
in part (b) much higher? Why would you expect this?
The probability in part (b) is much higher because the standard deviation is smaller for the x distribution.
The probability in part (b) is much lower because the standard deviation is smaller for the x distribution.
The probability in part (b) is much higher because the standard deviation is larger for the x distribution.
The probability in part (b) is much higher because the mean is larger for the x distribution.
The probability in part (b) is much higher because the mean is smaller for the x distribution.
In: Statistics and Probability