Question

In: Statistics and Probability

the population of cell phone battery life span is normally distributed with a mean of 450...

the population of cell phone battery life span is normally distributed with a mean of 450 charge cycles with a population standard deviation of 35 charge cycles

a) A single cell phone battery is selected at random. What is the probability that it will have a lifespan of 400 charge cycles or less?

b) A SRS of 50 cell phone batteries is selected, determine the probabiltiy that it will have an average life span of at least 460 charge cycles?

Please make it easy to read and show work so I may understand

Expert Solution

µ = 450

sd = 35

a)

= P(Z < -1.43)

= 0.0764

b) n = 50

= P(Z > 2.02)

= 1 - P(Z < 2.02)

= 1 - 0.9783

= 0.0217

orchestra answered 2 years ago

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