Combined Events flashcards

32 practice cards drawn from the Combined Events lessons. Tap a card to turn it over. Every answer is checked against the lesson it came from.

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Which symbol names the overlap, the homes that keep both pets?

from “Naming the Regions of a Venn Diagram”

How many homes keep a dog or a cat, or both?

15

from “Naming the Regions of a Venn Diagram”

Two dice are rolled. How many pairs total 10?

3

from “Possibility Diagrams”

Two dice are rolled. How many pairs total 5?

4

from “Possibility Diagrams”

A 2-by-1 patch sits on a 4-by-4 board. What is the chance the dart lands on the patch?

1/8

from “Chance from Areas”

A 3-by-2 patch sits on a 6-by-4 board. What is the chance the dart lands on the patch?

1/4

from “Chance from Areas”

One outcome has chance 2/8 and another has 3/8, and they cannot both happen. What is the chance of either one?

5/8

from “Mutually Exclusive Events”

Three mutually exclusive outcomes cover every case. Two have chances 1/8 and 1/8. What is the chance of the third?

6/8

from “Mutually Exclusive Events”

P(A) = 4/20, P(B) = 5/20 and P(A and B) = 2/20. What is P(A or B)?

7/20

from “The Addition Rule for Overlapping Events”

P(A) = 6/20, P(B) = 6/20 and P(A and B) = 3/20. What is P(A or B)?

9/20

from “The Addition Rule for Overlapping Events”

Two independent events have chances 1/4 and 1/5. What is the chance that both happen?

1/20

from “Independent Events”

Two independent events have chances 1/4 and 1/3. What is the chance that both happen?

1/12

from “Independent Events”

Two independent tries, each with a 1/4 chance of a win. What is the chance of winning both?

1/16

from “Tree Diagrams”

Two independent tries, each with a 1/5 chance of a win. What is the chance of winning both?

1/25

from “Tree Diagrams”

Two independent tries, each with a 1/4 chance of a win. What is the chance of at least one win?

7/16

from “The Chance of At Least One”

Two independent tries, each with a 1/6 chance of a win. What is the chance of at least one win?

11/36

from “The Chance of At Least One”

A bag holds 3 red counters and 2 blue. One red is taken out. What is the chance the next one is red?

2/4

from “Without Replacement”

A bag holds 5 red counters and 2 blue. One red is taken out. What is the chance the next one is red?

4/6

from “Without Replacement”

A bag holds 3 red counters and 3 blue. Two are drawn and neither is put back. What is the chance of one of each color?

3/5

from “Multiplying Along a Tree Without Replacement”

A bag holds 4 red counters and 2 blue. Two are drawn and neither is put back. What is the chance of one of each color?

8/15

from “Multiplying Along a Tree Without Replacement”

8 people play music and 5 of those also play sport. Given that a person plays music, what is the chance they play sport?

5/8

from “Conditional Probability”

7 people play music and 2 of those also play sport. Given that a person plays music, what is the chance they play sport?

2/7

from “Conditional Probability”

Which one means the chance of A, given that B has happened?

P(A | B)

from “Conditional Probability Notation”

P(A and B) = 4/18 and P(B) = 11/18. What is P(A | B)?

4/11

from “Conditional Probability Notation”

What is the chance of winning by switching?

2/3

from “The Monty Hall Problem”

What is the chance of winning by staying?

1/3

from “The Monty Hall Problem”

With 23 people, what is the chance two share a birthday?

about a half

from “The Birthday Paradox”

With 5 people, what is the chance two share a birthday?

very small

from “The Birthday Paradox”

If the illness becomes rarer, what happens to a positive test result?

more of the positives are false

from “Why a Positive Test Can Still Mean Healthy”

Screen 1000 people: 1 is ill, and the test is right 99 times in 100. About how many test positive?

about 11

from “Why a Positive Test Can Still Mean Healthy”

Which product is the numerator of P(ill | positive)?

0.001 × 0.99

from “Reversing a Tree: the Base-Rate Answer”

Why is the chance so small?

the well outnumber the ill a thousand to one

from “Reversing a Tree: the Base-Rate Answer”

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