The number of cell phone minutes used by high school seniors follows a normal distribution with a mean of 500 and a standard deviation of 50.What is the probability that a student uses more than 350 minutes?
A)0.001
B)0.999
C)0.618
D)0.382
E)None of the above

Question

Quizplus · Accepted Answer

To find the probability that a student uses more than 350 minutes, we first calculate the z-score: z = (350 - 500) / 50 = -3. Using the standard normal distribution table, the probability of z being less than -3 is approximately 0.001. Therefore, the probability of using more than 350 minutes is 1 - 0.001 = 0.999.

The Number of Cell Phone Minutes Used by High School