# Stats Library

## Statistics Assignment Library

1. ##### Solved: Grades in a statistics course and an operations research course taken simultaneously were as follows for a group of stud
Grades in a statistics course and an operations research course taken simultaneously were as follows for a group of students. Statistics Grade/ Operation Research Grade A B C Other A 25 6 17 13 B 17 16 15 6 C...
2. ##### Solved: The television show NBC Sunday Night Football broadcast a game between the Colts and Patriots and received a share of 22
The television show NBC Sunday Night Football broadcast a game between the Colts and Patriots and received a share of 22, meaning that among the TV sets in use, 22% were tuned to that game (based on data from Nielsen...
3. ##### Solved: Body mass index is calculated by dividing a person’s weight by the square of her height; it is a measure of the extent t
Body mass index is calculated by dividing a person's weight by the square of her height; it is a measure of the extent to which the individual overweight. For the population of middle aged men who later develop diabetes mellitis,...
4. ##### Solved: Combining test scores. The first Stats exam had a mean of 65 and a standard deviation of 10 points; the second had a mea
Combining test scores. The first Stats exam had a mean of 65 and a standard deviation of 10 points; the second had a mean of 80 and a standard deviation of 5 points. Derrick scored an 80 on both tests....
5. ##### Solved: Bob made 116 on his accounting midterm and 82 on his biology midterm. For the accounting midterm, th
Bob made 116 on his accounting midterm and 82 on his biology midterm. For the accounting midterm, the mean score was 102 with standard deviation 14. For the biology midterm, the mean score was 70 with standard deviation of 5....
7. ##### Solved: The heating bills for a selected sample of houses using various forms of heating are
The heating bills for a selected sample of houses using various forms of heating are given below. (Values are in dollars.) Natural Gas Central Electric Heat Pump 84 95 85 64 60 93 93 89 90 88 96 92 71...
8. ##### Solved: Suppose that the anthropologist of Exercise 7.43 wants the difference between the sample mean and the population mean to
Suppose that the anthropologist of Exercise 7.43 wants the difference between the sample mean and the population mean to be less than 0.4 inch, with probability 0.95. How many men should she sample to achieve this objective? Exercise 7.43 An...
9. ##### Solved: The time between calls to a plumbing supply business is exponentially distributed with a mean time between calls of
The time between calls to a plumbing supply business is exponentially distributed with a mean time between calls of 15 minutes. a. What is the probability that there are no calls within a 30-minute interval? b. What is the probability...
10. ##### Solved: The serum cholesterol levels of 12 to 14-year-olds follow a normal distribution with mean 162 mg/dl and standard deviati
The serum cholesterol levels of 12 to 14-year-olds follow a normal distribution with mean 162 mg/dl and standard deviation 28 mg/dl. What percentage of 12 to 14-year-olds have serum cholesterol values (a) 171 or more? (b) 143 or less? (c)...