The z-scores for X values greater than the mean are
negative.
True False
The normal distribution can be used to approximate a binomial
distribution when np is less than
5.
True False
The z-scores for X values greater than the mean are
negative.
True False
The time to fly between New York City and Chicago is uniformly
distributed with a minimum of 120 minutes and a maximum of 150
minutes. What is the mean?
A. 120 minutes
B. 150 minutes
C. 135 minutes
D. 270 minutes
The time to fly between New York City and Chicago is uniformly
distributed with a minimum of 120 minutes and a maximum of 150
minutes. What is the probability that a flight is more than 140
minutes?
A. 1.00
B. 0.5
C. 0.333 minutes
D. 10 minutes
For a standard normal distribution, what is the probability that
z is greater than 1.75?
A. 0.0401
B. 0.0459
C. 0.4599
D. 0.9599
What is the area under the normal curve between z = -1.0 and z =
-2.0?
A. 0.0228
B. 0.3413
C. 0.1359
D. 0.4772
The mean amount spent by a family of four on food per month is
$500 with a standard deviation of $75. Assuming that the food costs
are normally distributed, what is the probability that a family
spends less than $410 per month?
A. 0.2158
B. 0.8750
C. 0.0362
D. 0.1151
The standard normal probability distribution is unique because
it has:
A. A mean of 1 and any standard deviation
B. Any mean and a standard deviation of 1
C. A mean of 0 and any standard deviation
D. A mean of 0 and a standard deviation of 1
A binomial distribution has 100 trials (n = 100) with a
probability of success of 0.25 (p=0.25). We would like to find the
probability of 34 or more successes using the normal distribution
to approximate the binomial. What z-score should be
used?