EXST 2201 EXAM LATEST 2024-
2025 QUESTIONS WITH CORRECT
ANSWERS
[calc] For a side area in the schematic curve, how many lines are drawn and on which
side of the curve are they drawn? - Answer-Two lines on the same side.
[calc] Use the schematic curve and the z-table to find the z-score that separates the
bottom 86% of the individuals from the top 14% ? - Answer-z = +1.08
[calc] Use the schematic curve and the z-table to find what z-score separates the
bottom 5% of the individuals from the top 95% ? - Answer-z = -1.64
[calc] Use the schematic curve and the z-table to find what are the z-scores for the first
quartile (Q₁), and for the third quartile (Q₃). - Answer-(Q₁) is at z = -0.67, and (Q₃) is at z
= +0.67 .
[calc] What is the range of z-scores for the middle 82% of a population that follows the
standard normal curve? - Answer-Range of z-scores = (-1.34, +1.34) .
[defn] All normal curves look the same WHEN they are plotted on a graph in terms of
their mean +/- their standard deviations. - Answer-TRUE
[defn] x-Values have no units of measurement associated with them. - Answer-FALSE
[defn] How many normal curves are possible? - Answer-Infinitely many.
[know] Are the two equations below the same equation with one equation just a
reorganization of the other equation?
z=x−μσ�=�−��
x=μ+z∗σ - Answer-Yes, both equations are the same, just reorganized.
[know] In the Schematic Curve for x-values, please match the blanks from the right side
of the Schematic Curve with what type of number goes in each blank. - Answer-Top
blank. : An area under the curve.
Middle blank. : A z-score.
Bottom blank. : An x-value.
,[defn] The Schematic Curve for z-scores, with a second x-axis in terms of the mean and
standard deviation of the x-values, gives the Schematic Curve for x-values. - Answer-
TRUE
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $1,700, what percentage of home
buyers paid more than $152,074? - Answer-11.12%
[calc] In a recent past year, the scores of students taking the ACT college entrance test
were found to be distributed normally with a mean score of 18.6 and a standard
deviation score of 5.17. What is the probability that a randomly chosen student from this
population would have an ACT score higher than 21.6? - Answer-0.2810
[calc] In a city where the prices of new homes were found to be distributed normally with
a mean price of $150,000 and a standard deviation price of $900, what percentage of
these new homes cost less than $148,623? - Answer-6.30%
[calc] In a recent past year, the scores of students taking the ACT college entrance test
were found to be distributed normally with a mean score of 18.6 and a standard
deviation score of 5.85. What is the probability that a randomly chosen student from this
population would have an ACT score lower than 21? - Answer-0.6591
[calc] In a recent past year, the scores of students taking the ACT college entrance test
were found to be distributed normally with a mean score of 18.6 and a standard
deviation score of 5.85. What is the probability that a randomly chosen student from this
population would have an ACT score higher than 10? - Answer-0.9292
[calc] Intelligent Quotient (IQ) scores are standardized for population to have a mean
score of 100 and a standard deviation score of 15. With this knowledge, what percent of
the population are eligible to join the Mensa organization (need IQ > 130)? - Answer-
2.28%
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are priced between $161,000 and $172,000? - Answer-0.1359
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $1,1,00, what percentage of new
homes are mid priced (between $146,500 and $151,500)? - Answer-91.24%
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are mid priced (between $125,000 and $139,000)? - Answer-?
, [calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are priced between $145,000 and $155,000? - Answer-0.3472
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are priced between $139,000 and $175,000? - Answer-0.8297
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are mid priced (between $150,000 and $175,000)? - Answer-0.4884
[calc] The times to complete a mile long race for boys in a local secondary school was
known to be normally distributed with a mean time of 460 seconds and a standard
deviation time of 60 seconds. With this population, what time separates the fastest 10%
of the boys from the other 90%. Note that a faster boy completes the race in less
seconds. - Answer-383.3 seconds.
[calc] The times to complete a mile long race for boys in a local secondary school was
known to be normally distributed with a mean time of 460 seconds and a standard
deviation time of 60 seconds. With this population, what time separates the fastest 50%
of the boys from the slowest 50%. Note that a faster boy completes the race in less
seconds. - Answer-?
[calc] The times to complete a mile long race for boys in a local secondary school was
known to be normally distributed with a mean time of 460 seconds and a standard
deviation time of 60 seconds. With this population, what time separates the fastest 90%
of the boys from the other 10%. Note that a faster boy completes the race in less
seconds. - Answer-536.8 seconds.
[calc] In a factory packaging corn chips, the weight of corn chips put into each bag by a
dispensing machine was distributed normally with a mean weight of 48.5 ounces and a
standard deviation weight of 0.2 ounces. What weight of corn chips separates the
lightest 67% of the bags from the other 33%? - Answer-48.59 ounces.
[calc] At a local community college, the length of time it takes for a student to find a
parking place was distributed normally with a mean time of 5.5 minutes and a standard
deviation time of 1.0 minutes. What time separates the quickest 75.8% times to find a
parking space from the longest 24.2% times? - Answer-6.2 minutes.
[calc] In a beer bottling plant, the volume of beer put in a bottle by a beer filling machine
is distributed normally with mean 12.30 liquid ounces and standard deviation 0.04 liquid
ounces. What volume separates the smallest 1.5% volumes from the other 98.5%? -
Answer-12.21 liquid ounces.
2025 QUESTIONS WITH CORRECT
ANSWERS
[calc] For a side area in the schematic curve, how many lines are drawn and on which
side of the curve are they drawn? - Answer-Two lines on the same side.
[calc] Use the schematic curve and the z-table to find the z-score that separates the
bottom 86% of the individuals from the top 14% ? - Answer-z = +1.08
[calc] Use the schematic curve and the z-table to find what z-score separates the
bottom 5% of the individuals from the top 95% ? - Answer-z = -1.64
[calc] Use the schematic curve and the z-table to find what are the z-scores for the first
quartile (Q₁), and for the third quartile (Q₃). - Answer-(Q₁) is at z = -0.67, and (Q₃) is at z
= +0.67 .
[calc] What is the range of z-scores for the middle 82% of a population that follows the
standard normal curve? - Answer-Range of z-scores = (-1.34, +1.34) .
[defn] All normal curves look the same WHEN they are plotted on a graph in terms of
their mean +/- their standard deviations. - Answer-TRUE
[defn] x-Values have no units of measurement associated with them. - Answer-FALSE
[defn] How many normal curves are possible? - Answer-Infinitely many.
[know] Are the two equations below the same equation with one equation just a
reorganization of the other equation?
z=x−μσ�=�−��
x=μ+z∗σ - Answer-Yes, both equations are the same, just reorganized.
[know] In the Schematic Curve for x-values, please match the blanks from the right side
of the Schematic Curve with what type of number goes in each blank. - Answer-Top
blank. : An area under the curve.
Middle blank. : A z-score.
Bottom blank. : An x-value.
,[defn] The Schematic Curve for z-scores, with a second x-axis in terms of the mean and
standard deviation of the x-values, gives the Schematic Curve for x-values. - Answer-
TRUE
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $1,700, what percentage of home
buyers paid more than $152,074? - Answer-11.12%
[calc] In a recent past year, the scores of students taking the ACT college entrance test
were found to be distributed normally with a mean score of 18.6 and a standard
deviation score of 5.17. What is the probability that a randomly chosen student from this
population would have an ACT score higher than 21.6? - Answer-0.2810
[calc] In a city where the prices of new homes were found to be distributed normally with
a mean price of $150,000 and a standard deviation price of $900, what percentage of
these new homes cost less than $148,623? - Answer-6.30%
[calc] In a recent past year, the scores of students taking the ACT college entrance test
were found to be distributed normally with a mean score of 18.6 and a standard
deviation score of 5.85. What is the probability that a randomly chosen student from this
population would have an ACT score lower than 21? - Answer-0.6591
[calc] In a recent past year, the scores of students taking the ACT college entrance test
were found to be distributed normally with a mean score of 18.6 and a standard
deviation score of 5.85. What is the probability that a randomly chosen student from this
population would have an ACT score higher than 10? - Answer-0.9292
[calc] Intelligent Quotient (IQ) scores are standardized for population to have a mean
score of 100 and a standard deviation score of 15. With this knowledge, what percent of
the population are eligible to join the Mensa organization (need IQ > 130)? - Answer-
2.28%
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are priced between $161,000 and $172,000? - Answer-0.1359
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $1,1,00, what percentage of new
homes are mid priced (between $146,500 and $151,500)? - Answer-91.24%
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are mid priced (between $125,000 and $139,000)? - Answer-?
, [calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are priced between $145,000 and $155,000? - Answer-0.3472
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are priced between $139,000 and $175,000? - Answer-0.8297
[calc] For a city where the prices of new homes were distributed normally with a mean
price of $150,000 and a standard deviation price of $11,000, what proportion of new
homes are mid priced (between $150,000 and $175,000)? - Answer-0.4884
[calc] The times to complete a mile long race for boys in a local secondary school was
known to be normally distributed with a mean time of 460 seconds and a standard
deviation time of 60 seconds. With this population, what time separates the fastest 10%
of the boys from the other 90%. Note that a faster boy completes the race in less
seconds. - Answer-383.3 seconds.
[calc] The times to complete a mile long race for boys in a local secondary school was
known to be normally distributed with a mean time of 460 seconds and a standard
deviation time of 60 seconds. With this population, what time separates the fastest 50%
of the boys from the slowest 50%. Note that a faster boy completes the race in less
seconds. - Answer-?
[calc] The times to complete a mile long race for boys in a local secondary school was
known to be normally distributed with a mean time of 460 seconds and a standard
deviation time of 60 seconds. With this population, what time separates the fastest 90%
of the boys from the other 10%. Note that a faster boy completes the race in less
seconds. - Answer-536.8 seconds.
[calc] In a factory packaging corn chips, the weight of corn chips put into each bag by a
dispensing machine was distributed normally with a mean weight of 48.5 ounces and a
standard deviation weight of 0.2 ounces. What weight of corn chips separates the
lightest 67% of the bags from the other 33%? - Answer-48.59 ounces.
[calc] At a local community college, the length of time it takes for a student to find a
parking place was distributed normally with a mean time of 5.5 minutes and a standard
deviation time of 1.0 minutes. What time separates the quickest 75.8% times to find a
parking space from the longest 24.2% times? - Answer-6.2 minutes.
[calc] In a beer bottling plant, the volume of beer put in a bottle by a beer filling machine
is distributed normally with mean 12.30 liquid ounces and standard deviation 0.04 liquid
ounces. What volume separates the smallest 1.5% volumes from the other 98.5%? -
Answer-12.21 liquid ounces.
