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 =

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.