few_shots: 
Example 1:
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?


Concept/skill: 
Recognize and represent proportional relationships between quantities.

Answer: 
No. Usually problems that teach recognizing and representing proportional relationships between quantities involve deciding whether two quantities are in a proportional relationship or identifying the constant of proportionality, and then representing proportional relationships by equations or explaining proportional relationship using coordinate graphs.

Example 2:
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
$$-\frac{1}{4}$$


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

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:
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?


Concept/skill: 
Analyze and solve pairs of simultaneous linear equations.

Answer: 
Yes. The last three rows of the table in the first problem involves solving pairs of simultaneous linear equations. The second word problem can also be represented as two simultaneous linear equations.

Now, does the problem or activity shown below enable students to learn the full intent of the following concept or skill?

shot_info: fl_problem_000972_neg_0

6

fl_problem_001097_pos_0

7

fl_problem_001392_pos_0

8
standard_description: Recognize volume as an attribute of solid figures and understand concepts of volume measurement.
problem_activity: Narrative
The purpose of this activity is for students to estimate the number of shipping containers on a fully loaded cargo ship. Then they make many assumptions about the arrangement of the containers on the boat to come up with a better estimate.
Launch
Groups of 2
Display image.
“How many containers are on the cargo ship?”
“What is an estimate that’s too high?” “Too low?” “About right?”
1 minute: quiet think time
Record responses.
Activity
“A cargo ship can hold many more than 60 containers. The second image is a picture of a cargo ship that is fully loaded.“
5 minutes: independent work time
“Discuss your estimates and assumptions with your partner.”
2 minutes: partner discussion
Monitor for students who are making different assumptions:
The ship is fully loaded.
Some of the space is taken up with structures.
There are more containers below deck that we can’t see.
All containers are the same size.
the specific side lengths of the shipping containers
Student Facing
How many containers are on the cargo ship?
[IMG]
Record an estimate that is:
|                    too low                     |                  about right                   |                    too high                    |
|------------------------------------------------|------------------------------------------------|------------------------------------------------|
| \(\phantom{\hspace{2.2cm} \\ \hspace{2.2cm}}\) | \(\phantom{\hspace{2.2cm} \\ \hspace{2.2cm}}\) | \(\phantom{\hspace{2.2cm} \\ \hspace{2.2cm}}\) |
How many containers are on the cargo ship?
[IMG]
Record an estimate that is:
|                    too low                     |                  about right                   |                    too high                    |
|------------------------------------------------|------------------------------------------------|------------------------------------------------|
| \(\phantom{\hspace{2.2cm} \\ \hspace{2.2cm}}\) | \(\phantom{\hspace{2.2cm} \\ \hspace{2.2cm}}\) | \(\phantom{\hspace{2.2cm} \\ \hspace{2.2cm}}\) |
What assumptions were you making when you came up with your estimates?
Student Response
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Activity Synthesis
Invite students to share their estimates and any assumptions they made.
“How could you improve your estimate?” (Recreate the ship using a model. Check the height, width, and length of the container arrangement. See how many are on one side of the ship and multiply that to get a closer estimate.)


aligns: no