OPRE 6301 TEST 2 QUESTIONS AND ANSWERS 2026

OPRE 6301 TEST 2 LATEST
1. What is the probability that the sample proportion will be greater than
0.34?


2. What is the probability that the sample proportion will be between
0.196 and 0.354?


3. What is the probability that the sample proportion will be less than
0.25?


4. What is the probability that the sample proportion will be less than
0.10? - ANSWERS-1. 0.0359


2. 0.8411


3. 0.5


4. 0.0014


An infinite population has a mean of 73 and a standard deviation of 43.
A sample of size 121 is taken at random from this population. The
standard error of the sample mean equals: - ANSWERS-3.909 ± 0.1%
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, OPRE 6301 TEST 2 LATEST

*As the sample size becomes larger, the sampling distribution of the
sample mean approaches a


Normal Distribution.
Poisson distribution
binomial distribution
hypergeometric distribution - ANSWERS-Normal Distribution.


If all possible samples of size n are drawn from an infinite population
with a mean of 52 and a standard deviation of 17, then the standard error
of the sample mean equals 3 for samples of size: - ANSWERS-32.111 ±
0.1%


If two random samples of sizes 30 and 36 are selected independently
from two populations with means 78 and 85, and standard deviations 12
and 15, respectively, then the mean of the difference is equal to:


−7
7 - ANSWERS-−7


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, OPRE 6301 TEST 2 LATEST
If two random samples of sizes 30 and 36 are selected independently
from two populations with means 78 and 85, and standard deviations 12
and 15, respectively, then probability that the mean of the 1st sample
will be larger than the mean of the 2nd sample is


0.1169


0.2133


0.0176


0.9823 - ANSWERS-0.0176


In a large university, 20% of the students are business majors. A random
sample of 100 students is selected, and their majors are recorded.


1. Compute the standard error of the proportion.


2. What is the probability that the sample contains at least 12 business
majors?

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, OPRE 6301 TEST 2 LATEST
3. What is the probability that the sample contains less than 15 business
majors?


4. What is the probability that the sample contains between 12 and 14
business majors? - ANSWERS-1. 0.04


2. 0.9772


3. 0.1056


4. 0.044


The average lifetime of a light bulb is 3,000 hours with a standard
deviation of 696 hours. A simple random sample of 36 bulbs is taken.


1. What is the standard deviation of the sampling distribution?


2. What is the expected value?




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