Question

A consumer magazine is testing the lives of two kinds of flashlight batteries. Britelite battery claims...

A consumer magazine is testing the lives of two kinds of flashlight batteries. Britelite battery claims to give more life in normal use but is more costly than ordinary batteries. The magazine randomly purchases 50 Britelite batteries and 50 ordinary batteries. The Britelite batteries are found to have a mean life of 17.5 months of normal use with a standard deviation of 1.1 months. The ordinary batteries have a mean life of 14.7 months of normal use with a standard deviation of 1.3 months. Find a 95% confidence interval for the time difference in the lives of the batteries.  

Math   Statistics-And-Probability   
0 0
Add a commentTranscribed image text
Next >

Homework Answers

Answer #1

0 0
Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Log In

Sign Up

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A battery company produces typical consumer batteries and claims that their batteries last at least 100...
A battery company produces typical consumer batteries and claims that their batteries last at least 100 hours, on average. Your experience with their batteries has been somewhat different, so you decide to conduct a test to see if the company’s claim is true. You believe that the mean life is actually less than the 100 hours the company claims. You decide to collect data on the average battery life (in hours) of a random sample and obtain the following information:...
The lives​ (in hours of continuous​ use) of 100 randomly selected flashlight batteries​ are:       6.95−7.45 1      ...
The lives​ (in hours of continuous​ use) of 100 randomly selected flashlight batteries​ are:       6.95−7.45 1       7.45−7.95 9       7.95−8.45 20       8.45−8.95 36       8.95−9.45 21       9.45−9.95 12       9.95−10.45 1 a. Find the mean of the battery lives. b. Find the standard deviation of the battery lives.nothing hrs ​(Type an integer or a decimal. Round to two decimal​ places.)
the mean life of a name brand aa battery is 19 hours. a consumer group is...
the mean life of a name brand aa battery is 19 hours. a consumer group is interested in determining if generic aa batteries have a shorter mean life. this group tested a random sample of 9 generic AA batteries resulting in a mean life of 17.4 hours with a standard deviation of 1.5 hours. you may assume that battery lives follow a normal distribution. At 1% level of significance, do the generic AA batteries have a mean life shorter than...
A popular flashlight that uses two D-size batteries was selected, and several of the same models...
A popular flashlight that uses two D-size batteries was selected, and several of the same models were purchased to test the "continuous-use life" of D batteries. As fresh batteries were installed, each flashlight was turned on and the time noted. When the flashlight no longer produced light, the time was again noted. The resulting "life" data from Rayovac batteries had a mean of 21.8 hours. Assume these values have a normal distribution with a standard deviation of 1.38 hours. (Give...
A popular flashlight that uses two D-size batteries was selected, and several of the same models...
A popular flashlight that uses two D-size batteries was selected, and several of the same models were purchased to test the "continuous-use life" of D batteries. As fresh batteries were installed, each flashlight was turned on and the time noted. When the flashlight no longer produced light, the time was again noted. The resulting "life" data from Rayovac batteries had a mean of 20.4 hours. Assume these values have a normal distribution with a standard deviation of 1.5 hours. (Give...
A battery company claims that its batteries last an average of 100 hours under normal use....
A battery company claims that its batteries last an average of 100 hours under normal use. After several complaints that the batteries do not last this long, an independent testing laboratory decided to test the company’s claim with a random sample of 42 batteries. The data from the 42 batteries appeared to be unimodal and symmetric with a mean 97 hours and a standard deviation of 12 hours. Find a 90 % confidence interval for \muμ. Round your interval values...
A battery company claims that its batteries last an average of 100 hours under normal use....
A battery company claims that its batteries last an average of 100 hours under normal use. After several complaints that the batteries do not last this long, an independent testing laboratory decided to test the company’s claim with a random sample of 42 batteries. The data from the 42 batteries appeared to be unimodal and symmetric with a mean 97 hours and a standard deviation of 12 hours. Is this evidence that the company’s claim is false and these batteries...
A battery manufacturer claims that the batteries used in their electronic games will last an average...
A battery manufacturer claims that the batteries used in their electronic games will last an average of 36 hours. To certify this average, 12 batteries are tested each month. Calculate the t-value for a sample of 12 batteries that has a sample mean of 32.5 hours and a sample standard deviation of 5 hours. Assume the distribution of battery lives to be approximately normal, i.e. rules of symmetry apply. Round answer to 4 significant figures in the format: -1.234 The...
Grand Auto Corporation produces auto batteries. The company claims that its top-of-theline Never Die batteries are...
Grand Auto Corporation produces auto batteries. The company claims that its top-of-theline Never Die batteries are good, on average, for 65 months. A consumer protection agency tested 25 such batteries to check this claim. It found that the mean life of these 25 batteries is 63.4 months. Assume that the life of the batteries follow a normal distribution with standard deviation is 3 months. (a) Using a 1% significance level, test the hypothesis that the average life of Never Die...
A battery company claims that its batteries last an average of 100 hours under normal use....
A battery company claims that its batteries last an average of 100 hours under normal use. After several complaints that the batteries do not last this long, an independent testing laboratory decided to test the company’s claim with a random sample of 42 batteries. The data from the 42 batteries appeared to be unimodal and symmetric with a mean 97 hours and a standard deviation of 12 hours. Is this evidence that the company’s claim is false and these batteries...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT