1. Day 13 Independent and Dependent Events.notebook April 01, 2013
AIM: Independent and
Dependent Events
Do Now
Every Spring the Devins family rents a powerful vacuum cleaner
to clean all the carpets and rugs in their apartment. The cost is
$42.99 for a three day rental. Which equation below shows the
cost of the rental, r, for any number of days, d?
A r = 42.99d
B r = d + 42.99
C r = 14.33d
d r = 14.33d + 42.99
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2. Day 13 Independent and Dependent Events.notebook April 01, 2013
Anticipatory Set
Answer the following in complete sentences.
1.) Using your knowledge of American History, describe what
independence and dependence means.
Independence Dependence
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3. Day 13 Independent and Dependent Events.notebook April 01, 2013
Independent Events: One event does NOT effect the probability
of the other.
Dependent Events: One event does effect the probability
of the other.
State whether each set of events is independent or
dependent. Explain each answer.
1.) Erica flips a coin and then she rolls a die.
2.) John chooses a classmate for his group and then chooses
another classmate for his group.
3.) Jane rolls a six sided die and then rolls another six sided
die.
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4. Day 13 Independent and Dependent Events.notebook April 01, 2013
Theoretical Probability of Two Independent Events
P(A and B) =
1.) Find the theoretical probability of getting a head on a coin and
then rolling a five on a six sided die.
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5. Day 13 Independent and Dependent Events.notebook April 01, 2013
Theoretical Probability of Two Dependent Events
P(A and B) =
2.) Steve has three $1 bills, five $10 bills, and two $20 bills in his
wallet. If he picks one bill at a time at random, what is the
probability of him picking two $20 bills?
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6. Day 13 Independent and Dependent Events.notebook April 01, 2013
1.) A reading list contains 5 historical books and 3 science-fiction
historical
books. What is the probability that Alex will randomly choose a
historical book for his first report and a science-fiction book for
his second without replacement?
science-fiction
science-fiction
science-fiction
historical
historical
historical
historical
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7. Day 13 Independent and Dependent Events.notebook April 01, 2013
2.) Find the probability of choosing a green marble at random
from a bag a 5 green and 10 white marbles and then getting a tail
on a coin flip.
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8. Day 13 Independent and Dependent Events.notebook April 01, 2013
3.) Jill has seven quarters in her pocket. Of these, three are
“Delaware” quarters, two are “Georgia” quarters, one is a
“Connecticut” quarter, and one is a “Pennsylvania” quarter. Jill
removes one quarter at random and then removes a second quarter
at random without replacing the first quarter. What is the
probability that both will be “Delaware” quarters?
Connecticut
Delaware
Georgia
Pennsylvania
Delaware
Georgia
Delaware
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9. Day 13 Independent and Dependent Events.notebook April 01, 2013
4.) On a multiple choice test, each question had four possible
answers. A student does not know the answers to two questions,
so he guesses. What is the probability that the student will get
both answers wrong?
1.) The sky is:
a.) Blue b.) Black c.) Red d.) Orange
2.) 2 + 2 =
a.) 2 b.) 3 c.) 4 d.) 5
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10. Day 13 Independent and Dependent Events.notebook April 01, 2013
5.) In a bag there are 5 blue, 2 red, and 3 green marbles. What is the
probability of choosing a blue marble at random and then choosing a
green marble if you replace the first marble?
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11. Day 13 Independent and Dependent Events.notebook April 01, 2013
EXTRA PRACTICE
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12. Day 13 Independent and Dependent Events.notebook April 01, 2013
BEFORE YOU LEAVE
1.) Explain, in a complete sentence, whether the probability of
two events is greater or less than the probability of each
individual event.
2.) How are dependent and independent events similar and
different?
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13. Day 13 Independent and Dependent Events.notebook April 01, 2013
Mr. Tjersland's Math 7
Homework: Castle Assignment #7 due Wednesday
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14. Day 13 Independent and Dependent Events.notebook April 01, 2013
AIM: Independent and
Dependent Events
Theoretical Probability of Two Independent Events
P(A and B) = P(A) P(B)
2.) Find the probability of choosing a green marble at random
from a bag a 5 green and 10 white marbles and then getting a tail
on a coin flip.
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15. Day 13 Independent and Dependent Events.notebook April 01, 2013
AIM: Independent and
Dependent Events
Theoretical Probability of Two Dependent Events
P(A and B) = P(A) P(B after A)
1.) A reading list contains 5 historical books and 3 science-fiction
books. What is the probability that Alex will randomly choose a
historical book for his first report and a science-fiction book for
his second without replacement?
science-fiction
science-fiction
science-fiction
historical
historical
historical
historical
historical
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