7.SP.7_11_28_12_formatted

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7.SP.7
2012
Domain: Statistics & Probability
Cluster: Investigate chance processes and develop, use, and evaluate probability models.
Standards: 7.SP.7 Develop a probability model and use it to find probabilities of events. Compare probabilities from a
model to observed frequencies; if the agreement is not good, explain possible sources of the discrepancy.
a. Develop a uniform probability model by assigning equal probability to all outcomes, and use the model to determine
probabilities of events. For example, if a student is selected at random from a class, find the probability that Jane will be
selected and the probability that a girl will be selected.
b. Develop a probability model (which may not be uniform) by observing frequencies in data generated from a chance
process. For example, find the approximate probability that a spinning penny will land heads up or that a tossed paper cup will
land open-end down. Do the outcomes for the spinning penny appear to be equally likely based on the observed frequencies?
Essential Questions
 How do you find the
probability of more than
one event?
 How do you collect and
organize data?
 How do you make a
prediction?
 How do you compare
your prediction to the
actual outcome of an
experiment?
 How do you make a
conjecture based on the
outcome of an
experiment?
Enduring Understandings
Students will understand that:
 Experimental data gives
realistic estimates of the
probability of an event.
 Probabilities are useful for
predicting what will happen in
the long run.
 The difference between
theoretical and experimental
probability.
 Use theoretical probabilities to
create a probability model.
• Observed frequencies can be
used to create a probability
model for the data generated
Activities, Investigation, and Student Experiences
Activity:
 Create a game based on a model, predict the winner, play
the game. Compare observed frequencies with the
prediction and explain discrepancies.
Activity:
 Create a table showing the potential outcomes of an
experiment or random process with their corresponding
probabilities in which all outcomes are equally likely
(uniform).
Activity:
 Using theoretical probability, students predict
frequencies of outcomes. Students need multiple
opportunities to perform probability experiments and
compare these results to theoretical probabilities.

Experiments can be replicated by the same group or by
compiling class data. Experiments can be conducted
using various random generation devices including, but
7.SP.7
 Why should you
compare experimental
and theoretical
probabilities to one
another?
Content Statements
Students will be able to:
 Develop and use a
probability model.
from a chance process.
• A probability model can be used
to find probabilities of events.
 Using the results of an
experiment can be used to
estimate the probability of an
event.
 Recognize an
appropriate design to
conduct an experiment
with simple probability
events.
 Approximate the
probability of an
event(s) by collecting
data and performing an
experiment.
2012
not limited to, bag pulls, spinners, number cubes, coin
toss, and colored chips.

Students can collect data using physical objects or
graphing calculator or web-based simulations.

Students can also develop models for geometric
probability (i.e. a target).
Example:
 If Mary chooses a point in the square, what is the
probability that it is not in the circle?
Solution:
The area of the square would be 12 x 12 or 144 units
squared. The area of the circle would be 113.04 units
squared. The probability that a point is not in the circle
would be 30.96/144 = 21.5%
 Compare theoretical to
experimental probability
Assessments
Problem Task
The results of a spinner experiment are 50% red,
10% blue, 20% yellow, and 20% green. Draw the spinner.
Skill-based Task:
Example:
 Jason is tossing a fair coin. He tosses the coin ten times
and it lands on heads eight times. If Jason tosses the coin
an eleventh time, what is the probability that it will land
on heads?
7.SP.7
Juan rolled 15 fours when rolling a fair die 60 times. Would you
expect this result? Justify your answer.
2012
Solution:
The probability would be 1/2. The result of the eleventh
toss does not depend on the previous results.
Performance Assessment Tasks:
Fair Game?
Counters
Problems of the Month:
Activity:
 Devise an experiment using a coin to determine whether
a baby is a boy or a girl. Conduct the experiment ten
times to determine the gender of ten births. How could a
number cube be used to simulate whether a baby is a girl
or a boy or girl?
Friends you can count on
Got your Number
Fair Games
Party Time
Diminishing Return
Activity:
 Conduct an experiment using a Styrofoam cup by tossing
the cup and recording how it lands.
 How many trials were conducted?
 How many times did it land right side up?
 How many times did it land upside down?
 How many times did it land on its side?
 Determine the probability for each of the above results.
Online Activities:
 Marble Mania
 Random Drawing Tool
 Rolling the Dice
 Mathematics relevant to our world today
 Websites specific to 7.SP.7a
 Websites specific to 7.SP.7b
Equipment Needed:
Teacher Resources:
7.SP.7
2012

http://www.ncpublicschools.org/docs/acre/standards/com
mon-core-tools/unpacking/math/7th.pdf

http://www.schools.utah.gov/CURR/mathsec/Core/7thGrade-Core/7SP3.aspx

http://insidemathematics.org/index.php/7th-grade
Number Cube

http://www.khanacademy.org/math/probability
Spinner

http://www.yummymath.com/?s=7.sp.7

http://ccssmath.org/?page_id=671

http://ccssmath.org/?page_id=673

Interactive Whiteboard

Calculator

Computer

Marbles

Coin

Styrofoam Cup


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