Vocab
What is probability?
👉 Answer: The chance an event will happen
P(rolling a 1 on a die)
👉 1/6
10 successes out of 20
👉 1/2
Coin flip, What are the outcomes?
👉 {H, T}
On a normal dice-Expected: 60 rolls, P(6)
👉 10
What is theoretical probability?
👉 Answer: What should happen
Bag: 4 red, 6 blue → P(red)
👉 4/10 = 2/5
3 out of 12
👉 1/4
Die, What are the outcomes?
👉 {1,2,3,4,5,6}
On a dice, P(2 OR 5)
👉 2/6 = 1/3
What is experimental probability?
👉 Answer: What actually happens
Spinner: 5 equal sections → P(one section)
👉 1/5
15 out of 50
👉 3/10
2 coin flips, What are the outcomes?
👉 {HH, HT, TH, TT}
Fair vs unfair?
👉 Equal vs not equal chance
What is a sample space?
👉 Answer: All possible outcomes
P(rolling even number on die)
👉 3/6 = 1/2
Why are large samples better?
👉 More accurate
Shirt (red, blue), pants (jeans, shorts)
How many outcomes?
👉 4 outcomes
If Mrs. Messer had a bag with 6 marbles (2 of each color (Red, blue, green)), a normal dice, and a fair coin. What is the probability of a pink marble, roll a number 5, and get tails?
0
What does “certain” mean? (What is the probability value?)
👉 Answer: Probability = 1 or 100%
Dice: P(not rolling a 6)
👉 5/6
Experimental = 7/20, theoretical = 1/4 → close?
👉 Yes, somewhat close
How many outcomes for 3 choices × 2 choices?
👉 6
If Miss Clark had a bag with 6 marbles (2 of each color (Red, blue, green)), a normal dice, and a fair coin. What is the probability of a red marble, roll a number 3, and get heads?
1/36