Station 12 - Probability
At this station, you will use the manipulatives provided to solve both independent and dependent probability questions.
Let review probability:
*Probability is the likelihood that an event will take place.
Independent probability- the first event does not affect the second event
Dependent probability- the first event does affect the second event.
When determining probability we often use the formula:
P= Favorable outcome
Possible outcome
Ex) The probability of getting heads when flipping one coin is:
P= 1 or 50%
2
The probability of two coins landing on heads is:
P=1 x 1 = 1 or 25%
2 2 4
To find the probability of two events occurring, multiply the probabilities of the two events together. We call this the Counting Principle.
When determining dependent probability, you must take into account that the second event is affected by the first event, which will likely change the number of outcomes.
Probability Name ______
1) What is the probability of rolling an even sum with two dice?
2) What is the probability of flipping a coin three times and getting heads all three times?
3) George has a bag of colored chips. Inside the bag are 5
red chips, 3 blue chips, 2 green chips. Hew draws out two chips in a row without replacement. What is the number of
outcomes?
4) Clarence has five coins. 3 quarters, 2 dimes, one penny. If he draws one coin out and it is a quarter, what is the probability he will select a quarter the second time he chooses a coin.
5) Max has a cube with faces 1 through 6 and a spinner with 10 sections labeled 0-9. He will roll the number cube, and then spin the spinner. What is the probability that both results will be the number 5?
6) Carla will spin two spinners, both numbers 0-9. If the second spinner stops on the same number as the first spinner, Carla will win a prize. What is the probability that Carla will win a prize?
7) There are 4 blue marbles and 6 red marbles in a bag. Molly will take out 2 marbles at random. If the first marble she takes out is red, what is the probability the second marble will be blue?
8) Michael has five pictures to arrange on her phone. How many possible arrangements are there for his five pictures?
9) There is a 40% chance of rain on Monday and a 30% chance of rain on Tuesday. What is the probability it will rain on both days?
10) There are 20 red apples and 20 green apples in a box. Lisa is going to take out three apples without looking. If the first 2 apples are red, what is the probability the third apple will be green?