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: Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.
problem_activity: Problem 1
Elena and Zack want some change to buy penny candy. Their mom keeps rolls of 10 pennies to give to them for just this purpose. Their mom gives them 5 rolls and 4 loose pennies. How can Zack and Elena split the change they got from their mom evenly?
Problem 2
Elena used base-ten diagrams to find 3.72 ÷ 3. She started by representing 3.72.
[IMG]
She made three groups, each with 1 one. Then, she put the tenths and hundredths in each of the three groups. Here is her diagram for 3.72 ÷ 3.
[IMG]
Elena’s diagram for 3.72 has 7 tenths. The one for 3.72 ÷ 3 has only 6 tenths. Why?
Where did the extra hundredths (small squares) come from?
How would Elena calculate 95.6 ÷ 4?
Problem 3
Andre calculated 95.6 ÷ 4 using a method that was different from Elena’s method.
|           He started by writing the dividend, 95.6, and the divisor, 4.            | He then subtracted 4 groups of different amounts from 95.6, starting with 4 groups of 20... |                   …then 4 groups of 3, and then 4 groups of 0.9.                   |                 Andre calculated 20 + 3 + 0.9 and then wrote 23.9.                 |
|------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------|------------------------------------------------------------------------------------|
| .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2019/09/22/g5u6l9at3a.png |     .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2019/09/22/g5u6l9at3b.png      | .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2019/09/22/g5u6l9at3c.png | .. image:: https://d37su8u1z9ynie.cloudfront.net/uploads/2019/09/22/g5u6l9at3d.png |
Andre subtracted 80.0 from 95.6. What does the 80 represent?
Andre wrote 3.0 above the 20.0 and then subtracted 12.0 from 15.6. How is the 12.0 related to the 3.0?
What do the numbers 20.0, 3.0, and 0.9 represent?
What is the meaning of the 0.0 at the bottom of Andre’s work?
Problem 4
Solve. Show or explain your work.
0.96 ÷ 6 = ___________
9.85 ÷ 5 = ___________
24.08 ÷ 8 = ___________
64.8 ÷ 6 = ___________


aligns: yes