Find the mean and the standard deviation of typing speed

Reference no: EM13982851

1. Total annual textbook sales in a certain discipline are normally distributed. Forty-?ve percent of the time, sales are above 671,000 copies, and 10% of the time, sales are above 712,000 copies. Find the mean and the variance of annual sales.

2. Typing speed on a new kind of keyboard for people at a certain stage in their training program is approximately normally distributed. The probability that the speed of a given trainee will be greater than 65 words per minute is 0.45. The probability that the speed will be more than 70 words per minute is 0.15. Find the mean and the standard deviation of typing speed.

Reference no: EM13982851

Questions Cloud

Laxland and workland are two identical countries : Laxland and Workland are two identical countries except that people in Workland work twice as hard of those in Laxland. Under all the usual HO assumptions what would be your prediction of the patterns of trade between these two countries?

Estimate the volume of a human heart : Estimate the volume of a human heart (in mL) using the following measurements/assumptions: Blood flow through the aorta is approximately 15.5 cm/s. The diameter of the aorta is approximately 3.0 cm.

Meera corporation comparative balance sheets : All other changes in noncurrent account balances had a direct effect on cash flows, except the change in accumulated depreciation. The land was sold for $4,890.

Find mean and standard deviation of number : The agency found that 10% of the time, over 1,000 people respond immediately after a mailing, and 50% of the time, at least 650 people respond right after the mailing. Find the mean and the standard deviation of the number of people who respond fo..

Find the mean and the standard deviation of typing speed : The probability that the speed will be more than 70 words per minute is 0.15. Find the mean and the standard deviation of typing speed.

Out of bounds when the process is in control : Assuming a normal distribution of item values, what percentage of values would you expect to be out of bounds when the process is in control? Accordingly, how would you de?ne "too many"? What do you think is the rationale for this practice?

How much of insurance would mia buy : (i) What is Mia's expected utility? What is the expected value and the variance of her income? (ii) What is Mia's risk premium? (iii) Suppose that Mia; is offered an insurance policy at the rate p=0.25 How much of insurance would Mia buy?

Paying particular attention to the ethical implications : Required: Write a report addressing the parameters included in the 415 Ethics Rubrics, paying particular attention to the ethical implications of this situation. Come to a conclusion as to what you should do

Probability bounds on the number of people : For reservation purposes, the agency's management wants to ?nd the number of people such that the probability is 0.85 that at least that many people will sign up. It also needs 0.80 probability bounds on the number of people who will sign up for t..

User Account

All Pages