few_shots: 
Example 1:
Concept/skill: 
Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations.

Problem/activity:
You’re mixing ingredients for cookies. The recipe says to combine 6 tablespoons, or ¾ stick, of butter with 1 cup of sugar. You accidentally mix in a whole stick of butter (8 tablespoons) with the cup of sugar. How can you fix this?


Answer: 
Yes. This problem solves a real-world problem involving mixing ingredients for cookies. A student doing this problem would need to reason about equivalent ratios of butter amounts to sugar amounts.

Example 2:
Concept/skill: 
Apply and extend previous understandings of multiplication and division and of fractions to multiply and divide rational numbers.

Problem/activity:
For each pair of numbers, determine if the values are equivalent. Explain your reasoning for each one.
a.
$$-0.25$$
and
$$\frac{1}{-4}$$
b.
$$-\left ( \frac{1}{4} \right )$$
and
$$\frac{-1}{-4}$$
c.
$$\frac{-1}{4}$$
and
$$-\frac{1}{4}$$


Answer: 
Yes. This problem involves understanding fractions and division to divide rational numbers, such as 1, -4, 4, and -1. This problem also involves an understanding of multiplication: if p and q are integers, then -(p/q) = (-p)/q = p/(-q).

Example 3:
Concept/skill: 
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:
Problem 1
The table below contains single equations in a single variable, single equations in two variables, and pairs of simultaneous equations in two variables. Check the appropriate box to show whether there is no solution, exactly 1 solution, or if there is an infinite number of solutions.
|                                                          | **           No solution          ** | **           Exactly 1 solution          ** | **           Infinite number of solutions          ** |
|----------------------------------------------------------|--------------------------------------|---------------------------------------------|-------------------------------------------------------|
|                       $${9=4x+7}$$                       |                                      |                                             |                                                       |
|                       $${y=3y+5}$$                       |                                      |                                             |                                                       |
|                    $${y={x\over2}}$$                     |                                      |                                             |                                                       |
|                     $${3x+6y-9=0}$$                      |                                      |                                             |                                                       |
|    $${x=y}$$                        $${1.25x=1.25y}$$    |                                      |                                             |                                                       |
| $${9.9=6x+8y}$$                        $${9x=2.5y-8.8}$$ |                                      |                                             |                                                       |
| $${11x-2y=1.5}$$                        $${11x-2y=2.5}$$ |                                      |                                             |                                                       |
Problem 2
Kim has a small container and a large container as shown.
[IMG]
It takes 16 of the small containers to fill the large container. Three small containers leave 1.95 gallons of space in the big container.
What is the size of each of the two containers?


Answer: 
No. Completing neither of these problems requires replacing one equation by the sum of that equation and a multiple of the other equation.

Now, determine whether the following problem or activity can enable students to understand the concepts or skills in the provided description.

shot_info: fl_problem_000972_pos_0

6

fl_problem_001097_pos_0

7

fl_problem_001392_neg_0

8
standard_description: Understand a rational number as a point on the number line. Extend number line diagrams and coordinate axes familiar from previous grades to represent points on the line and in the plane with negative number coordinates.
problem_activity: Narrative
The purpose of this activity is for students to think of questions that can be answered using the data representation they create as they collect data from the class. Although there are two different sets of data, all of the questions students ask should be able to be answered using either data set. Questions are compiled during the synthesis and will be used in the following activity.
If necessary, use the provided blackline master instead of collecting data from the class. Cut the blackline master in half and give half the class data from Group A and the other half data from Group B.
Required Materials
Materials to Copy
Favorite Special Class Data
Launch
Groups of 2
“We are going to take another survey and ask questions about the data.”
Decide on a survey question the class would like to answer and three possible responses.
“Record the title of the data representation and each category.”
Demonstrate recording the titles.
Divide the class into Group A and Group B. Each partnership should have one person from each group.
“Group A is going to take the survey first. If you are in Group B, record the data in your book as I record it for all to see.”
Ask students in Group A the survey question and record the data on the table using tally marks and numbers.
“Now Group B is going to take the survey and Group A will record the data.”
Ask students in Group B the survey question and record the data on the table using tally marks and numbers.
Activity
“Now, think of as many questions as you can that can be answered using your data representation. Record your questions in your book if you would like.”
5 minutes: independent work time
Student Facing
Our favorite __________________________________________________
| category 1                     \(\phantom{\hspace{2.5cm} \\ \hspace{2.5cm}}\) | category 2                     \(\phantom{\hspace{2.5cm} \\ \hspace{2.5cm}}\) | category 3                     \(\phantom{\hspace{2.5cm} \\ \hspace{2.5cm}}\) |
|-------------------------------------------------------------------------------|-------------------------------------------------------------------------------|-------------------------------------------------------------------------------|
|                \(\phantom{\hspace{2.5cm} \\ \hspace{2.5cm}}\)                 |                                                                               |                                                                               |
Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Student Response.
Advancing Student Thinking
If students make statements instead of questions, consider asking:
“What is the question you want your partner to answer?”
“How could you finish this question, ‘How many students chose _____?’”
Activity Synthesis
Share and record the students’ questions about their data.
“Now we will ask our partner some of these questions.”


aligns: no