Conditional Probability with Two-Way Tables
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Objective
I can calculate conditional probabilities using two-way tables.
Part 1 of 4
Warm-up video
Mathispower4u · 4:18
We don't generate video — this one is by Mathispower4u on YouTube. The practice questions and exit ticket below were drafted by AI for this objective, and every question is editable in the teacher guide.
Part 2 of 4
Key concepts
3 concepts
- 1
Conditional probability is the probability of an event occurring, given that another event has already occurred.
- 2
To find the probability that a selected student would be female given they received an A on the test, you can divide the number of female students who received an A by the total number of students who received an A.
- 3
The formula for conditional probability is P(E₂|E₁) = P(E₂ and E₁) / P(E₁), where E₂ is the event we're interested in and E₁ is the given event.
Part 3 of 4
Practice
12 questions
What is conditional probability?
In a two-way table summarizing student grades and gender, what information do you use to calculate the probability of a student being male given they received a B?
Part 4 of 4
Exit ticket
Quick comprehension check
“In a class of students, some play sports and some are in the math club. The table below summarizes the data: | | Math Club | Not in Math Club | Total | |------------|-----------|--------------------|-------| | Plays Sports | 15 | 25 | 40 | | Doesn't Play Sports | 10 | 20 | 30 | | Total | 25 | 45 | 70 | If a student is selected at random, what is the probability that they play sports, given that they are in the math club? Express your answer as a simplified fraction.”
Sample answer included in the free materials
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