Question

In: Statistics and Probability

A factory producing light bulbs has made a recent change in the production process that will...

A factory producing light bulbs has made a recent change in the production process that will be less costly. The fear is that the mean life of the bulbs produced under the new process may be lower than it was before the change. Based upon historical records, it is known that the average lifetime of the bulbs produced before the change was 400 hours. The engineers in the plant are confident that only the mean might be affected by the change. A random sample of 55 light bulbs from the new process are selected and used until they burn out. The mean life of this sample was 350 hours and the standard deviation was 45. Using this sample do the following.

Based upon the confidence interval you constructed in part a), what can be said about the mean life of the bulbs from the new process compared to the mean of 400 hours in the old process? Give a reason for your answer

Solutions

Expert Solution


Related Solutions

Suppose the process of producing light bulbs is described by the function q = 2KL2, where...
Suppose the process of producing light bulbs is described by the function q = 2KL2, where q is the number of light bulbs produced, K is the number of capital inputs,and L is the number of units of labor. Suppose the price of capital is $5 per hour, the price of labor is $10 per hour and 16 units of output are produced. a) Write down the Lagrangian as a function of K, L and λ. b) Using the Lagrangian...
Compact fluorescent bulbs are much more efficient at producing light than are ordinary incandescent bulbs. They...
Compact fluorescent bulbs are much more efficient at producing light than are ordinary incandescent bulbs. They initially cost much more, but last far longer and use much less electricity. According to one study of these bulbs, a compact bulb that produces as much light as a 100 W W incandescent bulb uses only 23.0 W W of power. The compact bulb lasts 10000 hours, on the average, and costs $ $ 11.00, whereas the incandescent bulb costs only $ $...
Light Bulbs A red light bulb has been flashing forever, according to a Poisson process with...
Light Bulbs A red light bulb has been flashing forever, according to a Poisson process with rate r. Similarly, a blue bulb has been flashing forever, according to an independent Poisson process with rate b. Let us fix t to be 12 o'clock. 1 What is the expected length of the interval that t belongs to? That is, find the expected length of the interval from the last event before t until the first event after t. Here, an event...
A computer factory is planning to change their production process. They hire 18 new employees and...
A computer factory is planning to change their production process. They hire 18 new employees and half of them applies the new production process while the other half applies the old procedure. The length of time in minutes required for each employee to assemble the computer is recorded at the end of the month. The resulting measurements are shown in the following table. We know that the samples are independent. Assume normally distributed assembly times and assume that the variances...
Light emitting diode (LED) light bulbs have become required in recent years, but do they make...
Light emitting diode (LED) light bulbs have become required in recent years, but do they make financial sense? Suppose a typical 60-watt incandescent light bulb costs $.46 and lasts for 1,000 hours. A 15-watt LED, which provides the same light, costs $3.45 and lasts for 12,000 hours. A kilowatt-hour is 1,000 watts for 1 hour. Suppose you have a residence with a lot of incandescent bulbs that are used on average 500 hours a year. The average bulb will be...
Light emitting diode (LEDs) light bulbs have become required in recent years, but do they make...
Light emitting diode (LEDs) light bulbs have become required in recent years, but do they make financial sense? Suppose a typical 60-watt incandescent light bulb costs $.49 and lasts for 1,000 hours. A 15-watt LED, which provides the same light, costs $3.60 and lasts for 12,000 hours. A kilowatt hour of electricity costs $.125. A kilowatt-hour is 1,000 watts for 1 hour. However, electricity costs actually vary quite a bit depending on location and user type. An industrial user in...
Light emitting diode (LEDs) light bulbs have become required in recent years, but do they make...
Light emitting diode (LEDs) light bulbs have become required in recent years, but do they make financial sense? Suppose a typical 60-watt incandescent light bulb costs $.54 and lasts for 1,000 hours. A 15-watt LED, which provides the same light, costs $3.85 and lasts for 12,000 hours. A kilowatt hour of electricity costs $.130. A kilowatt-hour is 1,000 watts for 1 hour. However, electricity costs actually vary quite a bit depending on location and user type. An industrial user in...
Light emitting diode (LED) light bulbs have become required in recent years, but do they make...
Light emitting diode (LED) light bulbs have become required in recent years, but do they make financial sense? Suppose a typical 60-watt incandescent light bulb costs $.53 and lasts for 1,000 hours. A 15-watt LED, which provides the same light, costs $3.80 and lasts for 12,000 hours. A kilowatt-hour is 1,000 watts for 1 hour. Suppose you have a residence with a lot of incandescent bulbs that are used on average 500 hours a year. The average bulb will be...
Light emitting diodes (LED) light bulbs have become required in recent years, but do they make...
Light emitting diodes (LED) light bulbs have become required in recent years, but do they make financial sense? Suppose a typical 60-watt incandescent light bulb costs $.39 and lasts 1,000 hours. A 15-watt LED, which provides the same light, costs $3.10 and lasts for 12,000 hours. A kilowatt-hour of electricity costs $.115. A kilowatt-hour is 1,000 watts for 1 hour. If you require a return of 11 percent and use a light fixture 500 hours per year, what is the...
Production records indicate that 1.6​% of the light bulbs produced in a facility are defective. A...
Production records indicate that 1.6​% of the light bulbs produced in a facility are defective. A random sample of 20 light bulbs was selected. a. Use the binomial distribution to determine the probability that fewer than three defective bulbs are found. b. Use the Poisson approximation to the binomial distribution to determine the probability that fewer than three defective bulbs are found. c. How do these two probabilities​ compare?
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT