213k views
3 votes
g Two companies market new batteries targeted at owners of personal music players. Dura Tunes claims a mean battery life of 11 hours, while RockReady advertises 12 hours. Suppose the standard deviations are 2 hours for DuraTunes and 1.5 hours for RockReady. 1) What is the proportion of batteries produced by Dura that last less than 8 hours? 2) What is the proportion of batteries produced by RockReady that last less than 8 hours? 3) You are headed for 8 hours at the beach. Which battery would like to choose? why

User Livinston
by
5.8k points

1 Answer

4 votes

Answer:

1) Less than 13.6%

2) Less than .1%

3)RockReady

Step-by-step explanation:

THe standar deviation is a measure in statistics used to expres the dispersion of a set of values, so the standar deviation normally includes 34.1% of the values up and down the scale, so for example In Dura tunes 34.1% of the batteries would have 9 to 13 hours of battery life, to go down to 8 hours you would have to scale to the next deviation and that is of 13.6%, in RockReady is of 1.5 hours, and you would have to go down till the deviation of .1% to find the 4 hours needed in order for the batteries to have a battery life of 8 hours, that is why the best option statistically would be Rock Ready.

User Jan Stanstrup
by
5.4k points