{{ drag.val }}
Conditional Probability

The "Given" Condition

Conditional probability restricts our universe. Let's find .
Read as: "The probability of picking someone with a Hat, given they are a Cat."

{{ s1.phase === 1 ? 'Tap to filter: Select ALL the Cats' : 'Tap to select: Now select the Cats wearing Hats' }}
Great!

Reading the Table

When using a table, the "given" condition tells us which row or column to look at. Find .

Drag to build fraction
Soda 🥤 Juice 🧃 Total
Pizza 🍕
{{ s2.d.ps }}
{{ s2.d.pj }}
{{ s2.d.p_tot }}
Burger 🍔
{{ s2.d.bs }}
{{ s2.d.bj }}
{{ s2.d.b_tot }}
Total {{ s2.d.s_tot }} {{ s2.d.j_tot }} {{ s2.d.tot }}
GIVEN BURGER
{{ s2.numVal || '?' }}
{{ s2.denVal || '?' }}

The Multiplication Rule

The formula can be seen as calculating an area.

Slide to match target
{{ s3.valA.toFixed(1) }}
Width of the base
{{ s3.valBA.toFixed(1) }}
Portion of A that is also B
TARGET INTERSECTION
Area A
Match!

Calculate It

Use the definition to solve the problem.

"The probability of rain is {{ s4.pA }}. The probability of rain AND traffic is {{ s4.pAB }}. What is the probability of traffic given it is raining?"
Dial to solve
{{ s4.val.toFixed(2) }}
Tenths (0.1)
Hundredths (0.01)
CORRECT!
🎉

You Mastered It!

You've successfully filtered sample spaces, read two-way tables, and applied the conditional probability formula.