Question

A company claims that its tablet computers have an average recharge time of 3 hours. Using a random sample of 50 company tablet computers, a consumer group determines a mean recharge time of 2.5 hours with a standard deviation of 0.3 hours.

Answer 1

Solution:

The Statement made by company about it's tablet computer,

Average recharge time = 3 Hours

As, to check whether the company claim is illegal or true

A random sample of 50 company tablet computers, and their recharging time is noted.

As, we have taken random sample , so standard deviation will come into consideration whether company claim is true or false.

Mean recharge time of 50 company tablet computers=  2.5 hours

Standard deviation of 50 company tablet computers=  0.3 hours

So, Mean standard deviation =

   $2.5 \pm0.3\\\\ 2.5 -0.3 \leq {\text{Mean standard deviation}}\leq 2.5+0.3\\\\ 2.2\leq {\text{Mean standard deviation}}\leq 2.8$

So, Claim made by company , that its tablet computers have an average recharge time of 3 hours is  Approximately true.

As , there is fluctuation of (3 hours - 2.2 hours =3-2.12=48 minutes ) and (3 hours -2.8 hours=3-2.48=12 minutes), which is not so much ,so we can believe on this company and buy the product (that is tablet computers) of this company.

Answer 2

The answer for What is the null hypothesis, for this situation? is µ=3,  The answer for the following question is What is the alternative hypothesis, for this situation? is µ<3,  the answer for the following question The _________ hypothesis represents the statistical claim that the company’s tablet computers have an average recharge time of less than 3 hours. is alternative