standard_description: Prove that, given a system of two equations in two variables, replacing one equation by the sum of that equation and a multiple of the other produces a system with the same solutions.
problem_activity: Narrative
The purpose of this optional activity is for students to practice evaluating division expressions in order to make comparisons. Compare is a center that focuses on the procedural skills needed to solve single- and multi-step word problems. In this stage, students will use division to evaluate and compare quotients within 100.
This stage of the Compare center is used in grades 3, 4, and 5. When used in grade 3, remove the cards with two-digit divisors.
Required Materials
Materials to Copy
Compare Stage 4 Division Cards
Required Preparation
Create a set of cards from the blackline master for each group of 2. Remove the cards with two-digit divisors.
Launch
Groups of 2
Give each group of students a set of cards from the blackline master.
“Now let’s play Compare to practice what you learned about dividing numbers.”
“Take a minute to read the directions with your partner.”
1 minute: quiet think time
Answer any questions about the directions. If needed, play a turn with the class.
Activity
5–7 minutes: partner work time
If time permits, provide extra time to play Compare.
Student Facing
Play Compare with 2 players.
Shuffle the cards and
split the deck between the players.
Each player turns over a card.
Compare the values. The player with the greater value keeps both cards.
Play until you run out of cards. The player with the most cards at the end of the game wins.
Student Response
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Activity Synthesis
Display:
\(92 \div 4\)
and
\(72 \div 3\)
.
“Suppose these are the two cards you draw. How would you decide which expression has the greatest value?”


aligns: no