# Mean - practice problems

the arithmetic mean (simply the mean or average) is the sum of a collection of numbers divided by the count of numbers in the collection. The arithmetic mean is the most commonly used and readily understood measure of central tendency in a data set. It is a statistical characteristic of the center of a given data set.Arithmetic mean is a quantity very sensitive to extreme values, so the median and mode are also used in practice. Mode is the most common value. The median halves the ordered file.

#### Number of problems found: 459

- Six numbers

The average of 6 numbers is 3.95. the average of two of them is 3.4 while the average of other two is 3.85 . What is the average of remaining two numbers? - Weighted-average

Calculate the weighted-average cost of the following inventory purchases: Date Quantity; Purchased ; Cost per Unit May 4; 33; $12.25 May 11; 41; $13.87 May 29; 37; $11.99 - Dataset 3

Given dataset: 31, 28, 31,30,31,30,31,31,30,31,30,31 1. Construct a frequency table. 2. Construct a histogram. 3. Compute the mean. 4. Compute the median. 5. Find the mode. 6. Compute the midrange. 7. Compute the standard deviation. - Quartile statistics

Use the following data which was obtained from a study of weights of adult men to answer problems: Mean ; 192 lb ; First quartile ; 178lb Median; 185lb ; Third quartile ; 232 lb Mode ; 180 lb ; 86th percentile ; 239 lb Standard Deviation ; 23lb; ; a) What - The scores

The scores of 10 learners in a test arranged in ascending order is 12, 13, 13, a, (a + 3), (52 - 2a), (2a - 8), 23, 23 and 24. If the median mark is 20, find (a) value of a. (b) mean - The average 6

The average temperature dropped 16°C over a period of 5 weeks. What is the average change in temperature per week? - Carrots and potatoes

Juri is doing his weekly grocery shop and buying carrots and potatoes. He calculates that the average weight of a carrot is 60 g and the average weight of a potato is 125 g. Furthermore, he calculates that the average weight of the carrots and potatoes he - Z-score test

The weights of the fish in a certain lake are normally distributed with a mean of 11 lb and a standard deviation of 6. If 4 fish are randomly selected, what is the probability that the mean weight will be between 8.6 and 14.6 lb? Your answer should be a d - Summaries

A specialist teacher observes time taken by each of the students with learning disabilities to complete a psychological task. She summaries the times using the following: Time Taken(mins) ; 1-5; 6-10; 11-12; 16-20 No. of Student ; 2 ; 4 ; 12; 4 Using the - Consider 5

Consider the data below that shows the number of COVID cases of the fifteen barangays in Naga City: { 4, 7, 0, 3, 2, 1, 2, 1, 5, 4, 1, 3, 2, 3, 1}. What is the mean of the data? - The following

The following data represents the number of cases of coffee or filters sold by four sales reps in a recent sales competition. Sales Person; Gourmet; Single Cup; Filters; Total Connor; 142; 325; 30; 497 Paige ; 42; 125; 40; 207 Bryce ; 9; 100; - Decile

Find the 5.5th decile of the data: 62, 60, 37, 57, 55, 59, 57, 50, 49, 61 - A sample

A sample of 10 randomly selected students revealed the following grades in Business Statistics first test (in a marking scale of 0 to 100): 79, 63, 60, 45, 55, 58, 59, 62, 40, 68. Examine the data using groups and presenting: a) the Histogram of the absol - Suppose 6

Suppose the life span of a revolutionary light bulb is normally distributed with a mean life span of 70 thousand hours and a standard deviation of 3 thousand hours. If a light bulb is chosen at random: a) what is the probability the life span will be with - A person

A person buys 10 kg of commodity A at a rate of 2 kg per dollar, 20 kg of commodity b at a rate of 5 kilograms per dollar, and 30 kg of commodity C at a rate of 10 kg per dollar. Find the average price kg per dollar. - Divide line segment

Find the point P on line segment AB, such that |AP| = r |AB| . Coordinates of endpoints: A = (−2, 0, 1), B = (10, 8, 5), ratio r = 1/4. - Z score transformation

The annual salary of an entry level statistics major (in thousands of dollars) is normally distributed with mean of 75 and standard deviation of 12. X ∼ N ( μ = 75, σ = 12 ). What is the minimum salary a statistics major should aim for in order to earn am - The probability

The probability that a life bulb will have a life time of more than 682 hours is 0.9788. The probability that a bulb will have a life time of more than 703 hours is 0.0051. Find the probability that a bulb will last for more than 648 hours. - Two sigma

Khail took his math test and scored an 88. If the class average was 78 with a standard deviation of 5, what percent of students earned a grade that was HIGHER THAN Khail’s grade? - Estimate the mode

A medium-sized asset management firm has 56 fund managers. Each of these managers have their own portfolio. The percentage returns from the managers' portfolios are shown in the table below: Return percentage; Number of managers 0-10; 8 10-20; 18 20-30;

Do you have homework that you can't solve? Ask a question, and we try to solve it.