Transcript 6.1 Notes (1) - morgansmathmarvels

6.1 Notes (1)
Graphs of Normal
Probability Distributions
Normal Curve (aka “Bell Shaped” curve)
Ex. 1 For each of the curves give reasons why they are not normal curves.
Ex. 2 Use the normal curve below to answer the questions
a) Which point corresponds to the mean? What is the value of the mean?
b) Which point corresponds to μ+σ ? What is the value of σ ?
Ex. 3 Use the normal curve below to answer the questions
a) Do these distributions have the same mean? If so, what is it?
b) One curve has a σ = 3 and the other has a σ = 1. Which curve has
which σ?
Empirical Rule – (a.k.a. 68-95-99.7 rule) applies solely to normal distributions
μ ± σ contains approximately 68.2% of the data
μ ± 2σ contains approximately 95.4% of the data
μ ± 3σ contains approximately 99.7% of the data
Ex. 4 A vending machine automatically pours soft drinks into cups. The amount
of soft drink dispensed into a cup is normally distributed with mean of 7.6 oz.
and standard deviation of 0.4 oz.
a) Estimate the probability that the machine will not overflow an 8 oz. cup.
b) Estimate the probability that the machine will overflow an 8 oz. cup.
c) The machine has just been loaded with 850 cups. How many of these do you
expect will overflow when served?
Assignment
p. 244 #1-3, 5, 7-9