In: Math
a. Explain why you would also like to know the standard deviations of the battery lifespans before deciding which brand to buy.
b. Suppose the standard deviations are 2 hours for DuraTunes and 1.5 hours for RockReady. You are headed for 8 hours at the beach. Which battery is most likely to last all day? Explain.
PLEASE SHOW ALL WORK AND RATIONALE.
TYPED WORK ONLY PLEASE
NO HANDWRITTEN.
(A) We would like to know the standard deviations of the battery lifespans before deciding which brand to buy because standard deviation helps us in knowing the minimum and maximum battery life depending upon the different possible situations. So, it is important to know the standard deviation of the battery lifespans. Standard deviation will tells us which battery is more relaible for work and which is not reliable because small standard deviation provides higher reliability and higher standard deviation provides lower reliability.
(B) Mean battery life for Dura Tunes is 11 hours and RockReady is 12 hours
Assuming normal distribution
we can say that 95% of data the will fall within 2 standard deviation from the mean
standard deviation for Dura Tunes is 2 hours and 2 hours for RockReady
Calculation for DuraTune
Calculation for RockReady
So, it is clear that 95% of times DuraTune will last between 7 hours to 15 hours whereas RockReady will last between 9 hours to 15 hours
We need battery supply for at least 8 hours, So it is clear that RockReady is more reliable and it can give better battery life performance as compared to DuraTune.