Normal Distribution

The average,mean,range,x=, standard deviation, ect. All in pics below 5 problems. Thank you!!

The testing times for a group of college students were normally distributed with a mean of u = 30 minutes and a standard deviation of a = 2.5 minutes.
The bell curve below represents the distribution for testing times. The scale on the horizontal axis is equal to the standard deviation. Fill in the indicated boxes.
u= 30
o= 2.5
u-30-20
μσ
uo
u+ 20 ut 30
Used the Empirical Rule to complete the following statements:
68% of testing times were between
minutes and
minutes.
95% of testing times were between
minutes and
minutes.
99.7% of testing times were between
minutes and
minutes.
50% of testing times were below
minutes.
30
41
52
63
74
85
96
Based on the graph of this normal distribution,
a. The mean is
b. The median is
c. The mode is
d. The standard deviation is
49
54
59
69
74
79
64
Test Scores
Use the Empirical Rule to answer the following questions.
c.
a. The mean is
b. The standard deviation is
% of the test scores are between 59 and 69.
d. % of the test scores are between 54 and 74.
% of the test scores are between 49 and 79.
f. % of the test scores are between 64 and 69.
% of the test scores are less than 64.
h. % of the test scores are less than 69.
e.
نه له
A variable is normally distributed with mean 21 and standard deviation 3. Use your graphing calculator to find each of the following areas. Write your answers in decimal form. Round to the nearest thousandth
as needed.
a) Find the area to the left of 24.
b) Find the area to the left of 13.
c) Find the area to the right of 23.
d) Find the area to the right of 26.
e) Find the area between 13 and 30.
IQ is normally distributed with a mean of 100 and a standard deviation of 15.
a) Suppose one individual is randomly chosen. Find the probability that this person has an IQ greater than 95.
Write your answer in percent form. Round to the nearest tenth of a percent.
P(IQ greater than 95) = %
b) Suppose one individual is randomly chosen. Find the probability that this person has an IQ less than 125.
Write your answer in percent form. Round to the nearest tenth of a percent.
P(IQ less than 125) = %
c) In a sample of 800 people, how many people would have an IQ less than 110?
people
d) In a sample of 800 people, how many people would have an IQ greater than 140?
people