# Question: Suppose that the talk time on the Apple iPhone is

Suppose that the talk time on the Apple iPhone is approximately normally distributed with mean 7 hours and standard deviation 0.8 hour.

(a) What proportion of the time will a fully charged iPhone last at least 6 hours?

(b) What is the probability a fully charged iPhone will last less than 5 hours?

(c) What talk time would represent the cutoff for the top 5% of all talk times?

(d) Would it be unusual for the phone to last more than 9 hours? Why?

(a) What proportion of the time will a fully charged iPhone last at least 6 hours?

(b) What is the probability a fully charged iPhone will last less than 5 hours?

(c) What talk time would represent the cutoff for the top 5% of all talk times?

(d) Would it be unusual for the phone to last more than 9 hours? Why?

**View Solution:**## Answer to relevant Questions

The waist circumference of males 20 to 29 years old is approximately normally distributed, with mean 92.5 cm and standard deviation 13.7 cm. (a) Use the normal model to determine the proportion of 20- to 29-year-old males ...Imagine that a friend of yours is always late. Let the random variable X represent the time from when you are supposed to meet your friend until he shows up. Suppose your friend could be on time (x = 0) or up to 30 minutes ...Draw a normal curve with µ = 30 and σ = 10. Label the mean and the inﬂection points. In the game of golf, distance control is just as important as how far a player hits the ball. Michael went to the driving range with his range ﬁnder and hit 75 golf balls with his pitching wedge and measured the distance ...Determine the total area under the standard normal curve (a) to the left of z = -2.94 or to the right of z = 2.94 (b) to the left of z = -1.68 or to the right of z = 3.05 (c) to the left of z = -0.88 or to the right of z = ...Post your question