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CNSL 503/CNSL 503 FINAL STATISTICS EXAM LATEST 2026-2027
ACTUAL EXAM WITH COMPLETE QUESTIONS AND CORRECT
DETAILED ANSWERS (100% VERIFIED ANSWERS) |ALREADY
GRADED A+| ||PROFESSOR VERIFIED|| ||BRANDNEW!!!||
statistical power involves determining the probability of making
what type of error? - ANSWER-TYPE II ERROR (failing to reject a
false null hypothesis). Statistical power (β) is effect, sample, size,
significance level, number of tails of the test, and type of
hypothesis used.
which of the following tends to decrease statistical power? select
all that apply.
-large sample sizes
-two tailed tests
-high significance levels
-one tailed tests
-low α levels - ANSWER--two tailed tests -low α levels Note:
Large effect sizes, large sample sizes, one-tailed tests, and
higher significance levels tend to INCREASE statistical power.
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for a two tailed z-test with α = 0.05, which of the following is the
correct critical value?
+/- 1.96
+/- 3.30
+/- 2.575
+/- 1.86 - ANSWER-+/- 1.96 Note: need to memorize these
values, they aren't given on exam
a ________ is a range of values that is likely to contain the true
population mean. - ANSWER-CONFIDENCE INTERVAL - they
are centered around the mean and include a margin of error.
A lab technician is testing the reliability of one of the balances in
the lab. He weighs the same weigh boat with 2g of sugar 9 times
and obtains a mean measurement of 2.02 g (s = 0.04). Using a
critical value of 1.96, construct a 95% confidence interval for
these data. - ANSWER-confidence interval range = (x̄ - (z x s/√n)
to (x̄ + (z x s/√n)
(2.02 - 1.96 x 0.04 / √9) to (2.02 + 1.96 x 0.04 / √9)
= 1.994 to 2.046
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1.994 g < μ < 2.046 g
a group of 10 local ice cream shops believes that they sell more
ice cream than the average ice cream shop because they have a
better-quality product than most shops. The mean number of
customers they serve per day is 512. The national mean for ice
cream shops is 500 with a standard deviation of 24. Perform all 4
steps of a z-test to test this claim (α = 0.05) - ANSWER-Step 1)
H0: μ = 500
Ha: μ > 500
Step 2)
critical value = + 1.65
Step 3)
z = (X - μ / σ) / √n
= (512 - ) / √10 = 1.58
Step 4)
fail to reject null hypothesis. The z-score does not fall into the
critical region. There is not enough evidence to support that there
is likely a difference in the number of customers that frequent the
group of ice cream shops.
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a teacher administers a nutrition exam to her 45 students. the
mean score on the exam was 75 (μ = 75, σ = 8). The teacher
wants to determine the proportion of students who scored above
80 on the exam. Using the z-table, determine this proportion. -
ANSWER-z = X - μ / σ
= 80 -
= 0.63
the proportion of scores that lie below z = 0.63 (to the left) is
0.73565. This means that 73% of the values lie below the z-score
of 0.63. To find the scores above the z-score, 0.73565 needs to
be subtracted from 1. Therefore, 1 - 0.73565 = 0.26435 or
26.435%
true or false: the numerator of the t-score formula contains the
estimated standard error - ANSWER-false! the DENOMINATOR
contains the estimated standard error
the t-distribution for a __________ sample size more closely
resembles the z-distribution.
- small
CNSL 503/CNSL 503 FINAL STATISTICS EXAM LATEST 2026-2027
ACTUAL EXAM WITH COMPLETE QUESTIONS AND CORRECT
DETAILED ANSWERS (100% VERIFIED ANSWERS) |ALREADY
GRADED A+| ||PROFESSOR VERIFIED|| ||BRANDNEW!!!||
statistical power involves determining the probability of making
what type of error? - ANSWER-TYPE II ERROR (failing to reject a
false null hypothesis). Statistical power (β) is effect, sample, size,
significance level, number of tails of the test, and type of
hypothesis used.
which of the following tends to decrease statistical power? select
all that apply.
-large sample sizes
-two tailed tests
-high significance levels
-one tailed tests
-low α levels - ANSWER--two tailed tests -low α levels Note:
Large effect sizes, large sample sizes, one-tailed tests, and
higher significance levels tend to INCREASE statistical power.
,2|Page
for a two tailed z-test with α = 0.05, which of the following is the
correct critical value?
+/- 1.96
+/- 3.30
+/- 2.575
+/- 1.86 - ANSWER-+/- 1.96 Note: need to memorize these
values, they aren't given on exam
a ________ is a range of values that is likely to contain the true
population mean. - ANSWER-CONFIDENCE INTERVAL - they
are centered around the mean and include a margin of error.
A lab technician is testing the reliability of one of the balances in
the lab. He weighs the same weigh boat with 2g of sugar 9 times
and obtains a mean measurement of 2.02 g (s = 0.04). Using a
critical value of 1.96, construct a 95% confidence interval for
these data. - ANSWER-confidence interval range = (x̄ - (z x s/√n)
to (x̄ + (z x s/√n)
(2.02 - 1.96 x 0.04 / √9) to (2.02 + 1.96 x 0.04 / √9)
= 1.994 to 2.046
,3|Page
1.994 g < μ < 2.046 g
a group of 10 local ice cream shops believes that they sell more
ice cream than the average ice cream shop because they have a
better-quality product than most shops. The mean number of
customers they serve per day is 512. The national mean for ice
cream shops is 500 with a standard deviation of 24. Perform all 4
steps of a z-test to test this claim (α = 0.05) - ANSWER-Step 1)
H0: μ = 500
Ha: μ > 500
Step 2)
critical value = + 1.65
Step 3)
z = (X - μ / σ) / √n
= (512 - ) / √10 = 1.58
Step 4)
fail to reject null hypothesis. The z-score does not fall into the
critical region. There is not enough evidence to support that there
is likely a difference in the number of customers that frequent the
group of ice cream shops.
, 4|Page
a teacher administers a nutrition exam to her 45 students. the
mean score on the exam was 75 (μ = 75, σ = 8). The teacher
wants to determine the proportion of students who scored above
80 on the exam. Using the z-table, determine this proportion. -
ANSWER-z = X - μ / σ
= 80 -
= 0.63
the proportion of scores that lie below z = 0.63 (to the left) is
0.73565. This means that 73% of the values lie below the z-score
of 0.63. To find the scores above the z-score, 0.73565 needs to
be subtracted from 1. Therefore, 1 - 0.73565 = 0.26435 or
26.435%
true or false: the numerator of the t-score formula contains the
estimated standard error - ANSWER-false! the DENOMINATOR
contains the estimated standard error
the t-distribution for a __________ sample size more closely
resembles the z-distribution.
- small
