Simple Probability
Compound Probability
Predictions
Review
100
Answer as a percentage (round to the nearest tenth):
In a 12-sheet package of construction paper, there are 5 blue sheets.
What is the probability that you select a color that is NOT blue?
5 are blue.
7 are NOT blue.
7/12 = 0.58333...
about = 58.3%
100
To calculate compound probability, you find the probability of each event and you ______ them.
a. add
b. subtract
c. multiply
d. divide
c. multiply
100
If you flip a coin 25 times, what is the best prediction possible for the number of times it will land on tails?
The probability of landing on tails is 1/2.
1/2 of 25 is 12.5 times. So 12 or 13 times.
100
Add:
2/3 +3/4
2/3 = 8/12
3/4 = 9/12
8/12 + 9/12 = 17 / 12 = 1 5/12
200
Answer as a fraction in simplest terms:
A food company conducted a survey and found that 12 out of 20 people had french toast for breakfast yesterday.
What is the probability that a randomly selected person had french toast for breakfast?
Probability is wins/total
12/20 = 3/5 = 60%
200
If you spin this spinner and roll a dice, what is the probability that they will both land on 1?
1/6 x 1/2 = 1 / 12
200
If you spin this spinner 21 times, how many times would you expect to land on green?
Probability of landing on green is 2/7.
2/7 of 21 = 2/7 x 21 = 42/7 = 6 times!
200
Solve for b:
100b + 4500 = 6000
100b + 4500 = 6000
- 4500 - 4500
100b = 1,500
b = 1,500 / 100 = 15
300
Ms. D'Angelo's playlist is set to random. What is the probability that the next song will be Hip Hop or K-Pop?
5 + 15 = 20
20/30 = 2/3
300
You roll a red dice and blue dice at the same time.
What is the probability that the red dice lands on 4 and the blue dice lands on a number greater than 4?
Answer as a fraction in simplest terms.
1/6 x 2/6 = 2/36
2/36 = 1 / 18
300
You are playing a game in which you roll a dice and spin this spinner. You win if you land on a 4 and then spin onto to the green. If you play 60 times, how many times would you predict to win?
Probability of landing on 4 = 1/6
Probability of landing on green = 4/5
1/6 x 4/5 = 4/30
4 out of 30 = 8 out of 60.
So, the best prediction is 8 wins out of 60 games.
300
A train is traveling at a constant speed. After 3 hours, it travelled 183 miles. How can you determine the unit rate, in miles per hour?
Unit Rate = y / x
183 miles / 3 hours = 61 miles per hour
400
If you pick a marble at random, what is a result that will LIKELY happen?
A lot of possible answers, but all must include "or" (to add probabilities) or "not".
Examples:
NOT red
NOT yellow
NOT green
Blue or Yellow
Green or Yellow or Red
400
If you pick a card at random and spin the spinner, what is the probability that you pick a card with 7 and the spinner lands on the space that is NOT 7?
1/7 x 4/5 = 4/35
400
If you spin this spinner 55 times, how many more times would you expect to land on green than blue?
Green is 8/11
8/11 of 55 = 40
Blue is 3/11
3/11 of 55 = 15
So I would expect to land on green 25 more times than blue.
400
How do you know a graph on a coordinate plane represents a proportional relationship?
It is a straight line that goes through the origin.
500
Consider this spinner: What is an result that has a 40% chance of occuring?
40% = 40/100 = 4/10 = 2/5
So, the probability that it lands on an even number is 2/5.
The probability that it lands on a number greater than 5, less than 5, 3 or 6...
500
Using these TWO spinners, design a game that has a probability of winning that is greater than 50%.
Number greater than 1 on the first spinner and green OR yellow on the second spinner.
4/5 x 3/4 = 12/20 = 60%
500
You are playing a game in which you roll a dice and flip a coin. You win if you roll a number greater than 4 and land on Tails. If you play 60 times, what is the best prediction for the amount of times you would win?
Probability landing on number greater than 4 = 2/6
Probability of landing on tails = 1/2
Compound probability means MULTIPLY.
2/6 x 1/2 = 2/12 = 1/6
1/6 x 60 times playing the game = 10 wins!
500
The length of a rectangular garden is twice it's width. The perimeter of the rectangle is 63 feet. What is the length, in feet? What is the width, in feet?
(HINT: Perimeter means add up the sides)
(HINT 2: use a variable to write your equation. Then Solve)
Width = w
Length = twice the width = 2W
Perimeter = 63 feet = w + w + 2w + 2w
63 = 6w
w = 63/6 = 10.5 feet.
Length is 2 x 10.5 feet = 21 feet.
21 + 21 + 10.5 + 10.5 = 63 feet!