I. IDENTIFICATION.

A. Directions: Identify whether the given random variable is discrete or continuous.

1. The distance traveled between two countries.
2. The number of points in a volleyball match.
3. The body temperature of a sick person.
4. The number of items in a test.
5. The number of plates served at a restaurant.
B. Write the correct answer.

6. The standard deviation of 25 scores is 5 and the mean is 80. What is the variance?
7. Sample or Population. Respondents to a newspaper survey
8. Given the mean 𝜇 = 35 and standard deviation 𝜎 = 5 of a population. Find
the z-value that corresponds to a score 𝑥 = 40.
9. If a researcher wanted to give an equal chance to all the members of the
population around the City of Tanauan, what sampling technique must
he utilize?
10. What is the sampling process that divides the population into groups to
avoid the possibility of selecting samples coming from one kind?
11. Typically, after live presidential candidate debates on network television,
there appears a phone number for viewers to call and ask questions. What
sampling method could this be?
12. Box X and Box Y both contain the numbers 1, 2, 3, and 4. Suppose a
random variable R represents the sum when one number from each
bow is taken at a time, with replacement. What is the value of range
space?
13. Suppose a random variable T represents the positive difference of the
result of rolling a die and a constant number 1. What is the range space?
14. The random variable X is best described by a normal distribution with the
𝜇 = 20 and 𝜎 = 5. What is the z-score that corresponds to x = 26.5?
15. Forty students took a 50-item exam in Statistics and Probability and the
scores have a mean of 28 and a standard deviation of 3. Assume that
 the distribution of these scores is normally distributed. What is the
probability that the students scored 25 to 50?

16. Forty students took a 50-item exam in Statistics and Probability and the
scores have a mean of 28 and a standard deviation of 3. Assume that
the distribution of these scores is normally distributed. What is the
probability that the students scored 35 and above?
17. Forty students took a 50-item exam in Statistics and Probability and the
scores have a mean of 28 and a standard deviation of 3. Assume that
the distribution of these scores is normally distributed. What is the
probability that the students scored lower than 20?
18. A burger company wanted to see if people in Sto. Tomas liked their new
logo. Based on scenario, what is the population?
19. What is the sum of all the probability in a probability distribution?
20. If three coins are tossed and random variable gives the number of heads
that will appear, what is the range space?
21. Which case falls under the standard normal curve wherein one area is
subtracted from 50%?
22. A card is drawn from a standard deck of cards and the random variable
Y is assigned as the number of times a “numbered card” will appear.
What is the range space?
23. What will you do to find the area between two different sign z – values?
24. A distribution that shows a random variable value along its
corresponding probability values.
25. A representative of the population.
26. The mean score of the students on pre – assessment is 15 and the
standard deviation is 2. What was Elson’s raw score if his z – score is 1.5?
27. A researcher found out the population of Barangay Biga is 12,456. They
took a sample of 400 to participate in their survey. Using systematic
 sampling, find out the element the researchers should take for the
survey.
28. pair of dice is thrown, and the random variable X is assigned as the
number of times a “5” will appear. What is the probability that “5” will
only show once?
29. A dietician found that the average weight for women is 50 kg with the
standard deviation of 2 kg. What is the z – score of a woman with a
weight of 50 kg?
30. A dietician found that the average weight for women is 50 kg with the
standard deviation of 2 kg. If the weights are normally distributed, what
is the z -score of a woman with a weight of 58?
31. A dietician found that the average weight for women is 50 kg with the
standard deviation of 2 kg. How many kilograms corresponds to the z –
score of 0.5 of the weight of woman?
32. What is the area under the standard normal curve between 0 and
2.22?
33. What is the area under the standard normal curve to the left of z = -
1.2?
34. The top student of the class found that his score is at the 95th
percentile on his final exam. What does it imply?
35. You are told that your weight is the 55th percentile of all weights for the
students your age. What is the correct interpretation of this
information?
36. What is the mean of the given distribution?
X 0 1 2 3 4

Probability 0.1 0.3 0.3 0.2 0.1

 37. What is the standard deviation of the given distribution?

X 0 1 2 3 4

Probability 0.1 0.3 0.3 0.2 0.1

38. What is the probability of random variable 2?

X 0 1 2 3 4

Probability 0.1 0.3 0.2 0.1

39. A statistics that is used to project, generalize and test a certain

hypothesis.
40. A curve in which the maximum point occurs at 𝑥 = 𝜇 which is located at
the center.
41. “The International Dairy Foods Association (IDFA) wants to estimate the
average amount of calcium female teenagers consume. From a
random sample of 124 female teenagers, the IDFA obtained a sample
mean of 1062 milligrams of calcium consumed.” What is the sample in
the given scenario?
42. The result of quiz in mathematics are normally distributed with the
mean of 80 and standard deviation of 10. Find the raw such that 75%
of the cases are below it?
43. What is the mean of a normal curve where 99.7% of the values fall
between 60 and 84?
44. What is the standard deviation of a normal curve where 99.7% of the
values fall between 60 and 84?
45. A population of 500 scores has a mean of 86 and standard deviation
of 10. How many scores are above 106?