Probability: Sample Spaces, Compound Events and Experiments

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Mathematics · Math 7-8 / Pre-Algebra
SP-MATH68-017 · Free to print and use in your classroom · substituteplans.com
Page 2
Probability: Sample Spaces, Compound Events
and Experiments
Mathematics · Math 7-8 / Pre-Algebra · Grades 7 · 50 minutes
Time needed
50 minutes (one class period)
Prep
Copy the 2-page worksheet (one per student). Write P(event) = favorable ÷ total on the board.
Technology
None. Calculators are optional for arithmetic only.
Student
independence
High. Students work alone, then compare with a partner.
Copies to make
One 2-page worksheet per student
Materials
Pencils, Worksheet
Goal for today: Students will find simple and compound probabilities using sample spaces and will compare
theoretical and experimental probability.
Before the bell
☐ Copy the worksheet, one per student (2 pages).
☐ Write on the board: P(event) = number of favorable outcomes ÷ total number of equally likely
outcomes. Probability is always from 0 to 1.
☐ No dice or coins are needed. The sums table is completed on paper.
Say this to start
Good morning! Today’s math is probability, which tells how likely something is to happen. Students will fill in a table of
every possible dice total and then use it to answer questions. Everything is on paper, so you do not need any dice or
coins. The formula is on the board.

SubstitutePlans.com
Mathematics · Math 7-8 / Pre-Algebra
SP-MATH68-017 · Free to print and use in your classroom · substituteplans.com
Page 3
Run of show
Minutes
What you do
What students do
0–5
Take attendance as the school requires. Hand out
worksheets face down.
Settle in with a pencil.
5–12
Read this example aloud. A bag has 3 red and 1 blue
marble. P(red) = 3 ÷ 4 = 3/4. P(blue) = 1/4. The two add to
1. A probability of 0 means impossible and 1 means
certain.
Follow along and copy the example.
12–22
Tell students to fill in the Two-Dice Sums table (add the
number at the top to the number on the left) and answer
questions 1–2.
Complete all 36 cells and count the sums of
7.
22–38
Tell students to do questions 3–9. Walk the room and ask,
“How many outcomes are possible in all?”
Solve each problem and write answers as
fractions in simplest form.
38–46
Have students finish the Error Detective table and question
10. Read the answers aloud from the key.
Find the mistakes and check their own
work.
46–50
Collect all worksheets and stack them for the teacher.
Hand in the worksheet.
If things go wrong
• If a student does not know where to start on the table, tell them the top-left cell is 1 + 1 = 2.
• If a student wants to multiply instead of add on the table, point out the title says sums.
• If a student leaves a fraction unsimplified, accept it but encourage them to simplify.
• If a student finishes early, use the early finisher list.
Early finishers
• Use your table to find which sum is the most likely and which two sums are the least likely.
• Write one event with probability 0 and one event with probability 1 that you could describe about this
classroom.
Support and challenge
• Support: Allow calculators and complete the table and questions 1–2, 5 and 6 only.
• Challenge: Ask students to find the probability of drawing two blue marbles in a row without replacement
from a bag with 3 blue and 7 red (answer: 1/15).
Notes for the teacher (you fill this in)
Jot a few lines before you leave. A full Daily Sub Report is in the free Sub Survival Kit at SubstitutePlans.com.
How far the class got / what to pick up next:
Students who were especially helpful:

SubstitutePlans.com
Mathematics · Math 7-8 / Pre-Algebra
SP-MATH68-017 · Free to print and use in your classroom · substituteplans.com
Page 4
Anything the teacher should know: