Probability of an Event P(E)

A fair die is rolled. What is the probability of getting a number “3” ?

• 1/6

• 1/2

• 2/3

• 3/2

Answer explanation

S = { 1, 2, 3, 4, 5, 6}

n(S) = 6

There is only one "3" in a die.

Tags

CCSS.7.SP.C.7A

A fair die is rolled. What is the probability of getting a number that is even?

• 1/3

• 1/2

• 3/4

• 1/6

Answer explanation

S = {1, 2, 3, 4, 5, 6}

n(S) = 6

There are three even numbers out of six numbers in a die. These are: {2, 4, 6}

3/6 in lowest term is 1/2

Tags

CCSS.7.SP.C.7B

A fair die is rolled. What is the probability of getting a number less than 5?

• 1/3

• 1/4

• 2/3

• 1/6

Answer explanation

S = {1, 2, 3, 4, 5, 6}

n(S) = 6

There are four numbers which are less than 5. Those are: {1, 2, 3, 4}

4/6 in lowest term is 2/3

Tags

CCSS.7.SP.C.7A

A fair die is rolled. What is the probability of getting a number greater than 6?

• 1/6

• 2/3

• 1/2

• 0

Answer explanation

S = {1, 2, 3, 4, 5, 6}

n(S) = 6

There is NO number greater than 6 in a die.

Tags

CCSS.7.SP.C.5

A fair die is rolled. What is the probability of getting a number that is prime?

*PRIME NUMBERS are special numbers, greater than 1, that have exactly two factors, themselves and 1.

• 1/2

• 1/3

• 1/4

• 2/3

Answer explanation

S = {1, 2, 3, 4, 5, 6}

n(S) = 6

There are three prime numbers in a die. Those are: {2, 3, 5}

3/6 in lowest term is 1/2

Tags

CCSS.7.SP.C.7B

Fifteen identical cards are labelled 1 to 15. Find the probability of that a card drawn at random may be a number with the digit 1?

• 2/15

• 7/15

• 6/15

• 5/15

Answer explanation

S = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}

n(S) = 15

There are seven numbers with 1. Those are: {1 , 10, 11, 12, 13, 14, 15}

Tags

CCSS.7.SP.C.7B

Fifteen identical cards are labelled 1 to 15. Find the probability of that a card drawn at random may be a number that is divisible by 5?

• 1/4

• 1/2

• 1/5

• 1/15

Answer explanation

S = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}

n(S) = 15

There are three numbers which are divisible by 5. Those are: {5, 10, 15}

3/15 in lowest term is 1/5

Tags

CCSS.7.SP.C.7B

Fifteen identical cards are labelled 1 to 15. Find the probability of that a card drawn at random may be a number greater than 2 but less than 10?

• 2/15

• 4/15

• 9/15

• 7/15

Answer explanation

S = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}

n(S) = 15

There are 7 numbers which are greater than 2 but less than 10. Those are: { 3, 4, 5, 6, 7, 8, 9}

Tags

CCSS.7.SP.C.7B

• 1/5

• 2/15

• 1/2

• 2/3

Answer explanation

Tags

CCSS.7.SP.C.7B

Fifteen identical cards are labelled 1 to 15. Find the probability of that a card drawn at random may be double digits?

• 2/3

• 2/5

• 3/2

• 4/15

Answer explanation

S = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}

n(S) = 15

There are six double digit numbers between 1 to 15. These are: {10, 11, 12, 13, 14, 15}

6/15 in lowest term is 2/5

Tags

CCSS.7.SP.C.7B