STATISTICS AND PROBABILITY Midterm Review

A characteristic that is observable or measurable in every unit of the universe.

• a. Variable

• b. Population

• c. Universe

• d. Sample

It is a science that studies data to be able to make a decision.

• a. Probability

• b. Physical Science

• c. Earth and Life Sciences

• d. Statistics

A random variable that can take infinitely uncountable number of possible values, typically measurable quantities.

• a. continuous variable

• b. discrete variable

• c. probability

• d. probability distribution

Answer explanation

There are two types of quantitative variable: Discrete and Continuous. Discrete variables are countable and in whole numbers while continuous can be measured and can be expressed in decimals

It is a way to map outcomes of a statistical experiment determined by chance into number.

• a. random variable

• b. variable

• c. probability

• d. probability distribution

Which of the following is an example of qualitative variable?

• a. total family income

• b. amount of time last week you spent using the internet

• c. occupation of a person

• d. amount spent in pesos on food in one week

Answer explanation

Qualitative variables can be categorized. Out of the four questions, only the occupation of a person can be categorized.

Which of the following is a property of probability distribution of discrete variable?

• a. Probabilities should be confined between 0 and 2

• b. The sum of all the probabilities should be 100

• c. Probabilities should be confined between 0 and 1

• d. The sum of all the probabilities should be 2

Answer explanation

The sum of probabilities should add up to 1 or 100%, not 100 or 2.

It is a subgroup of a universe or of a population.

• a. Variable

• b. Population

• c. Universe

• d. Sample

Refer to the given probability distribution where Y is the number of pets a student has at home. What is the probability of selecting a student having 3 pets?

• a. 25

• b. 2.5

• c. 25%

• d. 30%

Answer explanation

Looking at the table, the percentage for the random variable 3 is 25%

It is referred to as a set of all possible values of a variable.

• a. Random Variable

• b. Population

• c. Universe

• d. Sample

Answer explanation

Population is a set of all possible values of a variable while a Sample is a set of all possible outcomes that can occur

The Engineering Department of Palompon did a listing of all buildings in their locality. If you are planning to gather the characteristics of these buildings, what is the universe in this data gathering activity?

• a. The Engineering Department

• b. Palompon residents

• c. Engineers of Palompon

• d. the buildings

Answer explanation

The population of a study does not always refer to a person, it could be inanimate objects. In this case, the buildings are which the researcher will get the characteristics in their study.