Question

(Question 8) 2 pts A process is normally distributed with a mean of 10.2 hits per minute and a standard deviation of 1.04 hits. If a randomly selected minute has 13.9 hits, would the process be considered in control or out of control? Out of control as this one data point is more than three standard deviations from the mean In control as only one data point would be outside the allowable range In control as this one data point is not more than three standard deviations from the mean Out of control as this one data point is more than two standard deviations from the mean Flag this Question

(Question 9) 2 pts The candy produced by a company has a sugar level that is normally distributed with a mean of 16.8 grams and a standard deviation of 0.9 grams. The company takes readings of every 10th bar off the production line. The reading points are 17.3, 14.9, 18.3, 16.5, 16.1, 17.4, 19.4. Is the process in control or out of control and why? It is out of control as the values jump above and below the mean It is in control as the data points more than 2 standard deviations from the mean are far apart It is in control as none of these data points is more than 3 standard deviations from the mean It is out of control as two of these data points are more than 2 standard deviations from the mean Flag this Question

(Question 10) 2 pts The toasters produced by a company have a normally distributed life span with a mean of 5.8 years and a standard deviation of 0.9 years, what warranty should be provided so that the company is replacing at most 5% of their toasters sold? 4.6 years 5.9 years 7.3 years 4.3 years Flag this Question

(Question 11) 2 pts A running shoe company wants to sponsor the fastest 5% of runners. You know that in this race, the running times are normally distributed with a mean of 7.2 minutes and a standard deviation of 0.56 minutes. How fast would you need to run to be sponsored by the company? 6.3 minutes 6.1 minutes 8.3 minutes 8.1 minutes Flag this Question

(Question 12) 2 pts The weights of bags of peas are normally distributed with a mean of 13.50 ounces and a standard deviation of 1.06 ounces. Bags in the upper 5% are too heavy and must be repackaged. What is the most that bag and weigh and not need to be repackaged? 15.36 ounces, 11.64 ounces, 15.24 ounces, 11.76 ounces

Answer 1

#8 Given .

Since 13.9 is greater than upper limit, the correct option is:

Out of control as this one data point is more than three standard deviations from the mean.

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#9 Given .

Since none of these data points, 17.3, 14.9, 18.3, 16.5, 16.1, 17.4, 19.4, is more than 3 standard deviations from the mean, the correct option is:

It is in control as none of these data points is more than 3 standard deviations from the mean.

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#10 Given . Let x years warranty should be provided so that the company is replacing at most 5% of their toasters sold. This means lowest 5% life span will lie below x. The z score corresponding to lowest 5% is .

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#11 Given . Let x minutes separates fastest 5% from rest. This means highest 5% time will lie above x. The z score corresponding to highest 5% is .

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#12 Given . Let x ounces separates upper 5% from rest. This means highest 5% weights will lie above x. The z score corresponding to highest 5% is .