Probability Quiz Review

Probability Quiz Review

Independent, Dependent, and Mutually Exclusive Events

Independent Probability

• Multiple events WITH REPLACEMENT

• Example: Probability of selecting a blue marble, PUTTING IT BACK, then probability of selecting a red marble

• MULTIPLY the fractions and reduce

• You try the independent probability practice questions on the next two slides

Multiple Choice

A bag contains 8 blue marbles, 7 green marbles, and 5 yellow marbles. Suppose you drew one marble from the bag above, replaced it and then drew a second marble. What is the probability of drawing a green, and then a blue marble.

• 4/5

• 43/400

• 15/20

• 7/50

Multiple Choice

There are 14 tiles with one letter from the word MATHEMATICIANS on each. You are now going to choose a letter, put it back and then choose another letter. Find the probability of choosing a vowel, and then NOT the letter T.

• 18/196

• 36/196

• 18/49

• 8/14

Dependent Probability

• Multiple events WITHOUT REPLACEMENT

• Example: Probability of selecting a face card from a deck, NOT PUTTING IT BACK, then probability of selecting an 8 from the same deck

• When finding the probability of the 2nd event, SUBTRACT what was removed during the first event

• MULTIPLY the fractions and reduce

• You try the dependent probability practice problems on the next two slides

Multiple Choice

Des buys a pack of Starbursts that has 3 orange, 6 pink, 1 yellow, and 5 red Starbursts. She puts the candy in the bowl. If she reaches in and grabs two Starbursts without putting one back, what is the probability that she will pick a pink and then a yellow?

• 1/35

• 7/210

• 6/225

• 2/75

Multiple Choice

What is the probability of picking a red marble and keeping it, picking another red marble and keeping it, then picking a blue marble?



• 2/105

• 3/343

• 2/63

• 4/210

Mutually Exclusive Events

• The probability of one thing OR a second with NO OVERLAP (can't occur at the same time)

• Example: Probability of selecting a queen or a 5 from a deck of cards

• No "overlap" because there are no queens that are also 5's

• Find the probability of each and ADD the fractions

• Now try the practice problems on the next two slides

Multiple Choice

Danny has 20 chocolates. 5 are milk chocolates, 10 are dark chocolates, and 5 are white chocolates. What is the probability of getting a milk chocolate or a dark chocolate?

• 3/4

• 1/2

• 1/15

• 3/10

Multiple Choice

If you roll one die, what is the probability of getting an odd number or a 4?

• 1/3

• 2/3

• 1/2

• 1/6

MIXED PRACTICE

The next set of practice problems are a mix of independent, dependent, and mutually exclusive events. Read the problem carefully to decide which type before solving.

Multiple Choice

Find the probability of choosing a student at random that plays an instrument OR a sport

• 1/2

• 21/20

• 13/20

• 4/5

Multiple Choice

If you spin two times, what is the probability of landing on green both times?

• 1/6

• 1/9

• 1/36

• 1/30

Multiple Choice

A bag contains 9 green marbles, 5 yellow marbles and 6 red marbles. You choose one marble. What is the probability of selecting a green or red marble?

• 8/15

• 6/11

• 2/3

• 3/4

Multiple Choice

You roll a 6-sided die. What is the probability of rolling an even number three times in a row?

• 3/100

• 1/2

• 1/6

• 1/8

Multiple Choice

A cookie jar has 3 DOZEN chocolate chip, 1 DOZEN peanut butter, and 2 DOZEN oatmeal cookies. If Megan chooses a cookie, does not replace it, then chooses another, what is the probability that she chooses a peanut butter then a chocolate chip cookie?

• 6/71

• 2/3

• 1/10

• 11/72

Multiple Choice

What is the probability of picking a blue marble, putting it back in the bag, then picking a red marble?

• 9/49

• 16/49

• 12/42

• 12/49

Multiple Choice

If you draw one card from a standard deck, what is the probability of drawing a spade or a red card?

• 13/52

• 26/52

• 39/52

• Not possible