MGMT 650 Final Exam Practice 1 | Questions and Answers | Fall 2025/2026 Update | 100% Correct -UMGC.

Q1
Confidence Interval - Definition


A confidence interval is random estimator of a population parameter value. It is typically computed at a 95%
confidence level such that 95% of all possible confidence intervals contain the true parameter value.


TRUE

Q3
Confidence Interval - Confidence and significance levels

Confidence level (%) = 100% - significance level α (%)

TRUE



Q4




Match

Increasing the sample size
Critical value for 95% confidence level and sample size 25 for confidence interval for mean
Critical value for 90% confidence level and DF=27
Critical value for 99% confidence level for proportion
Increasing the confidence level




SEE Row 5, Column AD for
Increasing the sample size 2. Narrows the Confidence Interval
the Proof)

Critical value for 95%
confidence level and sample size
4. 2.064 2.064 T.INV.2T(0.05,24)
25 for confidence interval for
mean

Critical value for 90%
5. 1.703 1.703 T.INV.2T(0.1,27)
confidence level and DF=27
Critical value for 99%
3. 2.576 2.576 NORM.S.INV(1-(0.01/2))
confidence level for proportion
SEE Row 5, Column AI for
Increasing the confidence level 1. Widens the Confidence Interval
the Proof)

, Q2
Confidence Interval - Relationship of width and level


y computed at a 95%
What happens if the confidence level is decreased or the significance level α is increased
meter value.
The confidence interval width decreases




1 Widens the confidence interval
2 Narrows the confidence interval
3 2.576
4 2.064
5 1.703
6 Has no effect on the width of the confidence interval
7 Decreases the critical value
8 1.96
9
1.645
10

2.069


11
1.706

12
none of the above

,ased or the significance level α is increased?




Q5


The lower confidence limit for a poll of 87 people with proportion 0.70 in favor at 99% confidence level and 3 decimal pla


Alpha 1% 1-.99
P 0.7 Given
1-P 0.3 1-.7
Conf. Level 99% Given
n 87 Given

SE 0.0491304 ((0.7*0.3)/87)^0.5
Critical Value 2.5758293 NORM.S.INV(1-0.01)
ME (SE * Crit. Val) 0.1265514 0.049*2.576

Lower Confidence Limit 0.573 0.7 - 0.127 {p} - 2.5758*sqr({p}*(1-{p})/{n}

, Confidence Level and Width of a Co



Confidence Level
Alpha
Sample Size
Degrees of Freedom
Critical Value (T-Stat)
X Bar
Standard Deviation
Standard Error
Margin of Error
Upper Bound
Lower Bound
Range of Width

As the confidence level is decreased, or th
evel and 3 decimal places is
increased, the width of the interval decre




8*sqr({p}*(1-{p})/{n})