# Worksheet: Probability of Simple Event

In this worksheet, we will practice finding the probability of a simple event and write it as a fraction.

Q1:

A bag contains 7 white marbles, 8 black marbles, and 7 red marbles. If a marble is chosen at random from the bag, what is the probability that it is white?

• A
• B
• C
• D

Q2:

What is the probability of rolling a number smaller than 2 on a regular dice?

• A
• B
• C
• D
• E

Q3:

Given that the probability of an event occurring is 0.87, what is the probability of the event not occurring?

Q4:

In a class, the probability that a student chosen at random is a girl is 0.34. What is the probability that a student chosen at random is NOT a girl?

Q5:

Given that the probability of a person being selected for a job is , what is the probability of that person NOT being selected?

Q6:

A spinner has 10 equal sections labeled from 1 to 10. Determine the probability of the pointer landing on 4 or 7.

• A
• B
• C
• D
• E

Q7:

A box contains 7 white balls, 3 black balls, and 8 red balls. What is the probability that a ball drawn at random is black?

• A
• B
• C
• D
• E

Q8:

If an event has a chance of occurring, what is the probability that it does not occur?

Q9:

Given that the probability a student passes their exams is , what is the probability a student fails?

• A
• B
• C
• D
• E

Q10:

The probability that an event occurs is 0.9. What is the probability that the event does not occur?

Q11:

Next week’s forecast predicts that there is a chance that it will rain. Describe the complementary event and its probability.

• AThere is a chance that it will not rain.
• BThere is a chance that it will rain.
• CThere is a chance that it will rain.
• DThere is a chance that it will not rain.
• EThere is a chance that it will not rain.

Q12:

If I roll a regular six-sided die, what is the probability that the score is an odd, prime number?

• A
• B
• C
• D

Q13:

If I roll a regular six-sided die, what is the probability that the score is divisible by 3?

• A
• B
• C1
• D

Q14:

State whether it is impossible, certain, or possible for it to rain gold.

• Aimpossible
• Bcertain
• Cpossible

Q15:

If a coin is flipped once, what is the probability of getting a tail?

• A
• B
• C
• D

Q16:

A card is selected at random from a pack of 16 cards which are numbered 1 to 16. What is the probability of the selected card having an even number?

• A
• B
• C
• D
• E

Q17:

Given that the probability of an event occurring is , what is the probability of the event not occurring?

• A
• B
• C
• D1

Q18:

A class contains 6 boys and 21 girls. If a pupil is selected at random, what is the probability they are a girl?

• A
• B
• C
• D
• E

Q19:

If the probability of an event occurring is , what is the probability that it does not occur?

• A
• B
• C
• D

Q20:

If a regular six-sided die is rolled twice, what is the probability of getting a 4 on the first roll?

• A
• B
• C
• D

Q21:

If a regular six-sided die is rolled twice, what is the probability of getting a 3 on the first roll?

• A
• B
• C
• D

Q22:

If I roll a regular six-sided die, what is the probability that the score is an odd number?

• A
• B
• C
• D

Q23:

If I roll a regular six-sided die, what is the probability that the score is 5?

• A
• B
• C
• D

Q24:

If I roll a regular six-sided die, what is the probability that the score is 6?

• A
• B
• C
• D

Q25:

If I roll a regular six-sided die, what is the probability that the score is 3?

• A
• B
• C
• D