Algebra 2 Probability, Normal Distribution and Z Score

What is the area under the curve to the left of z = 0.55 ?

• .2912

• .5500

• .9394

• .7088

An algebra 2 test has 6 multiple choice questions with four choices with one correct answer each. If we just randomly guess on each of the 6 questions, what is the probability that you get exactly 3 questions correct? (You need to figure out the p value first. It is not given to you.)

• 96.2%

• 13.2%

• 8.31%

• 25.0

Find the z-score value corresponding if the location is below the mean by 2 standard deviations

• +2.00

• -2.00

• +1.25

• -1.00

If the mean of a normal distribution is 50 and the standard deviation is 5, what percentage of the data falls between 45 and 55?

• 68%

• 95%

• 99.7%

• 50%

What is the probability that a score is under (left of) 1.73?

• .9484

• .9664

• .9573

• .9582

What percent of data on normal curve is between z=0 and z=1.23?

• 68%

• 12%

• 89%

• 39%

What is the probability of any z value between 0 and 2.2?

• 0.012

• 0.486

• 0.4895

• 0.988

The distribution of cholesterol levels in teenage boys is approximately normal with μ = 170 and σ = 30 (Source:

U.S. National Center for Health Statistics). Levels above 200 warrant attention. What percent of teenage boys

have cholesterol levels greater than 225?

• 46.64 %

• 3.36 %

• 6.06 %

• 56.13 %

An airline knows from experience that the distribution of the number of suitcases that get lost each week on a

certain route is approximately normal with μ = 15.5 and σ = 3.6. What is the probability that during a given

week the airline will lose less than 20 suitcases?

• 0.3944

• 0.1056

• 0.4040

• 0.8944

In a factory, the weight of the concrete poured into a mold by a machine follows a normal distribution with a mean of 1150 pounds and a standard deviation of 22 pounds. Approximately 95% of molds filled by this machine will hold weights in what interval?

• 1084 to 1216 pounds 

• 1106 to 1150 pounds 

• 1106 to 1194 pounds 

• 1128 to 1172 pounds