Example 2.9 In a certain large city, household annual incomes are considered approximately normally distributed with...
1) The household income in a certain community is normally distributed with a mean of $42,000 and a standard deviation of $5,000. The proportion of households with incomes of at least $50000 is between: a) 5% and 6% b) 44% and 45% c) 94% and 95% d) none 2) The actual weight of "8 oz. chocolate bar" produced by a certain machine are normally distributed with mean 8.1 oz. and standard deviation of 0.1 oz. only 5% of the bars...
dPrint Hide email 1) The incomes in a certain large population of high school teachers has a mean income μ-$70,000 and standard deviation σ-S6, 000. 50 teachers are selected at random from this population for a survey a) (5 pts) Based on the central limit theorem we would expect the distribution of the sample mean incomes to be approximately b) (5 pts) What is the mean of the sampling distribution of the mean (x )? c) (5 pts) What is...
The mean annual rainfall in a local city is approximately normally distributed with the a mean of 14 inches and a standard deviation of 1.5 inches. What is the probability that the annual rainfall will.. a.) Exceed 12 inches b.) Be less than 16 inches c.) Be between 16 and 20 inches
The lifetime of a certain brand of tires is approximately normally distributed, with a mean of 45,000 miles and a standard deviation of 2,500 miles. The tires carry a warranty for 40,000 miles.(Show work please) What proportion of the tires will fail before the warranty period? What proportion of the tires will fail after the warranty expires, but before they have lasted for 41,000 miles? Suppose a sample of 100 randomly selected tires are tested, what is the probability that...
Annual salaries for employees in a large company are approximately normally distributed with a mean of $50,000 and a standard deviation of $20,000. What percentage of company workers make under $40,000?
4. (6 points) The incomes in a certain large population of college teachers are distributed with a mean of $65,000 and a standard deviation of $12,000. Thirty-six teachers are selected at random from this population to serve on a committee a) Determine the sampling distribution of the mean income for samples of size 36. b) What is the probability that the selected teachers' average salary is less than $60,000?
Solve the problem. Annual precipitation in a certain city is normally distributed with a mean of 99 inches, and a standard deviation of 18 in. Find the probability that the mean annual precipitation during 35 randomly picked years will be less than 101.8 in.? Group of answer choices 0.8212 0.3212 0.9203 0.6788 0.1788
Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean equals 137 days and standard deviation equals 12 days. The probability that a random sample of size 17 will have a mean gestation period within 12 days of the mean is ? .
Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean p=231 days and standard deviation o = 12 days. Complete parts (a) through (f) below. (a) What is the probability that a randomly selected pregnancy lasts less than 227 days? The probability that a randomly selected pregnancy lasts less than 227 days is approximately (Round to four decimal places as needed) Interpret this probability. Select the correct choice below and fill in the answer...
Suppose the lengths of the pregnancies of a certain animal are approximately normally distributed with mean u = 282 days and standard deviation o = 20 days. Complete parts (a) through (f) below. (a) What is the probability that a randomly selected pregnancy lasts less than 274 days? The probability that a randomly selected pregnancy lasts less than 274 days is approximately 0.3446. (Round to four decimal places as needed.) Interpret this probability. Select the correct choice below and fill...