Random Variables

RANDOM VARIABLES AND PROBABILITY DISTRIBUTION

Illustrate a random variable (discrete or continuous).

Distinguish between a discrete and continuous  random variable.

Illustrate a probability distribution for a discrete random variable and its properties.

Compute probabilities corresponding to a given random variable.

​OBJECTIVES

Activity #1 What I know

This activity is not graded. However, please answer the questions accurately. Thank you!

Multiple Choice

If two coins are tossed once, which is NOT a possible value of the random variable for the number of heads?

• 0

• 1

• 2

• 3

Multiple Choice

Which of the following is a discrete random variable?

• Length of wire ropes

• Number of soldiers in the troop

• Amount of paint used in repainting the building

• Voltage of car batteries

Multiple Choice

Which formula gives the probability distribution shown by the table?

• P(X) = X

• P(X) = 1/X

• P(X) = X/3

• P(X) = X/5

Multiple Choice

How many ways are there in tossing two coins once?

• 4

• 3

• 2

• 1

Multiple Choice

It is a numerical quantity assigned to an experiment’s outcome.

• Random Variables

• Variable

• Probability

• Probability Distribution

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Classify the following random variables as discrete or continuous.

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The weight of the professional wrestlers

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The number of winners in lotto for each day

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The area of lots in an exclusive subdivision

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The speed of a car.

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The number of dropouts in a school per locality.

Determine the values of the random variables in each of the following

distributions.

​Please type your answer with comma to separate the number/s if necessary.

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Two coins are tossed. Let T be the number of tails that occur. Determine

the values of the random variable T.

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A meeting of envoys was attended by 4 Koreans and 2 Filipinos. If three envoys were selected at random one after the other, determine the values of the random variable F representing the number of Filipinos.

Activity #2 What's In

Identify the term being described in each of the following:

Multiple Choice

Any activity which can be done repeatedly under similar conditions

• Event

• Probability

• Experiment or Trial

• Outcome

• Sample Space

Multiple Choice

The set of all possible outcomes in an experiment

• Event

• Probability

• Experiment or Trial

• Outcome

• Sample Space

Multiple Choice

A subset of a sample space

• Event

• Probability

• Experiment or Trial

• Outcome

• Sample Space

Multiple Choice

The elements in a sample space

• Event

• Probability

• Experiment or Trial

• Outcome

• Sample Space

Multiple Choice

The ratio of the number of favorable outcomes to the number of possible outcomes

• Event

• Probability

• Experiment or Trial

• Outcome

• Sample Space

Multiple Choice

In how many ways can two coins fall?

• 4

• 6

• 8

• 12

• 36

Multiple Choice

If three coins are tossed, in how many ways can they fall?

• 4

• 6

• 8

• 12

• 36

Multiple Choice

In how many ways can a die fall?

• 4

• 6

• 8

• 12

• 36

Multiple Choice

In how many ways can two dice fall?

• 4

• 6

• 8

• 12

• 36

Multiple Choice

How many ways are there in tossing one coin and rolling a die?

• 4

• 6

• 8

• 12

• 36

Fill in the Blanks

WHAT'S NEW:

Mary Ann, Hazel, and Analyn want to know what numbers can be assigned for

the frequency of heads that will occur in tossing three coins.

Can you helpthem?

Thanks!

​Example

​Continuation of the Solution

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