SOLUTION: Please help me solve this equation. according to a report by Scarborough Research, the average monthly household cellular phone bill is $73. Supposed monthly household cell phon

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Question 1137235: Please help me solve this equation.
according to a report by Scarborough Research, the average monthly household cellular phone bill is $73. Supposed monthly household cell phone bills are normally distributed with a standard deviation of $11.
a. what is the probability that a randomly selected monthly cell phone bill is less than $95?
b. a. what is the probability that a randomly selected monthly cell phone bill is between 62 and $84?

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
z=(x-mean)/sd
<(95-73)/11 or <2
This probability is 0.9772.
Between 62 and 84 is between z=-1 and z=+1
This has probability 0.6827