few_shots: Example:
Problem/activity:
Task
Cruz and Erica were both getting ready for soccer.
Cruz ran 1 lap around the school.
Erica ran 3 laps around the playground.
Erica said,
I ran more laps, so I ran farther.
Cruz said,
4 laps around the school is 1 mile, but it takes 12 laps around the playground to go 1 mile. My laps are much longer, so I ran farther.
Who is right? Draw a picture to help you explain your answer.


Standard options: 
A. Explain why a fraction a/b is equivalent to a fraction (n × a)/(n × b) by using visual fraction models, with attention to how the number and size of the parts differ even though the two fractions themselves are the same size. Use this principle to recognize and generate equivalent fractions.
Grade 4 expectations in this domain are limited to fractions with denominators 2, 3, 4, 5, 6, 8, 10, 12, and 100.
B. Compare two fractions with different numerators and different denominators, e.g., by creating common denominators or numerators, or by comparing to a benchmark fraction such as 1/2. Recognize that comparisons are valid only when the two fractions refer to the same whole. Record the results of comparisons with symbols >, =, or <, and justify the conclusions, e.g., by using a visual fraction model.
Grade 4 expectations in this domain are limited to fractions with denominators 2, 3, 4, 5, 6, 8, 10, 12, and 100.


Your response, in json format:
{
  "explanation": "This task asks students to compare two fractions that are equal. The two fractions have different numerators and denominators (e.g. 1/4 and 3/12). The students need to explain why the two fractions are equal by drawing a picture, which involves using visual fraction models.",
  "answer": "A, B"
}

Now, assign the following problem or activity to one or more relevant standards it aligns with.
shot_info: im_task_000212

4
options: Solve real world problems involving multiplication of fractions and mixed numbers, e.g., by using visual fraction models or equations to represent the problem.

Interpret a fraction as division of the numerator by the denominator (a/b = a ÷ b). Solve word problems involving division of whole numbers leading to answers in the form of fractions or mixed numbers, e.g., by using visual fraction models or equations to represent the problem. For example, interpret 3/4 as the result of dividing 3 by 4, noting that 3/4 multiplied by 4 equals 3, and that when 3 wholes are shared equally among 4 people each person has a share of size 3/4. If 9 people want to share a 50-pound sack of rice equally by weight, how many pounds of rice should each person get? Between what two whole numbers does your answer lie?

Interpret multiplication as scaling (resizing), by:
- Explaining why multiplying a given number by a fraction greater than 1 results in a product greater than the given number (recognizing multiplication by whole numbers greater than 1 as a familiar case); explaining why multiplying a given number by a fraction less than 1 results in a product smaller than the given number; and relating the principle of fraction equivalence a/b = (n×a)/(n×b) to the effect of multiplying a/b by 1.
- Comparing the size of a product to the size of one factor on the basis of the size of the other factor, without performing the indicated multiplication.

Apply and extend previous understandings of division to divide unit fractions by whole numbers and whole numbers by unit fractions. (Students able to multiply fractions in general can develop strategies to divide fractions in general, by reasoning about the relationship between multiplication and division. But division of a fraction by a fraction is not a requirement at this grade.)

Apply and extend previous understandings of multiplication to multiply a fraction or whole number by a fraction.
problem_activity: Narrative
The purpose of this activity is for students to write expressions for and find the area of shaded regions whose side lengths are a unit fraction and a non-unit fraction. Students look at a series of diagrams with an increasingly large shaded region so they can look for and make use of structure (MP7).
It is important to relate the work here to what students have already learned about the product of a unit fraction and a unit fraction and this is the goal of the synthesis. For example, students have seen that
\(\frac{1}{5} \times \frac{1}{3} = \frac{1}{15}\)
. Since
\(\frac{6}{5}\)
is 6
\(\frac{1}{5}\)
s, the product
\(\frac{6}{5} \times \frac{1}{3}\)
will be 6
\(\frac{1}{15}\)
s or
\(\frac{6}{15}\)
.
MLR8 Discussion Supports.
Prior to solving the problems, invite students to make sense of the situations and take turns sharing their understanding with their partner. Listen for and clarify any questions about the context.
Advances: Listening, Conversing
Launch
Groups of 2
Display image A from the student workbook.
“What is a multiplication expression that represents the shaded region?”(
\(\frac{2}{5} \times \frac{1}{3}\)
,
\(2 \times \frac{1}{15}\)
)
“How does the diagram represent your expression?”(There is
\(\frac{2}{5}\)
of the first row shaded and that row is
\(\frac{1}{3}\)
of the square. There are 2 shaded pieces and each is
\(\frac{1}{15}\)
of the whole square.)
Activity
3–5 minutes: independent work time
3–5 minutes: partner discussion
Monitor for students who:
notice that the product of the numerators represents how many pieces of the square are shaded.
notice that the product of the denominators represents the number of pieces in the whole square.
Student Facing
Write a multiplication expression that represents the shaded region in each diagram.
A
[IMG]
B
[IMG]
C
[IMG]
What patterns do you notice in the multiplication expressions?
Han wrote this equation to represent the area of the shaded region. Explain how the diagram represents the equation.
\(\phantom{2.5cm} \\ \frac {6}{5} \times \frac {1}{3} = \frac {6}{15}\)
[IMG]
Student Response
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Advancing Student Thinking
If students write mathematically correct multiplication expressions that do not represent the product of a unit fraction and a non-unit fraction, write this type of multiplication expression that represents the diagram and ask “How does this expression represent the area of the shaded region in the diagram?”
Activity Synthesis
Ask previously selected students to share the patterns they noticed in the table.
Display the expression from the last problem:
\(\frac {6}{5} \times \frac {1}{3} = \frac {6}{15}\)
.
“How does the diagram show
\(\frac {1}{3}\)
?” (The first row of pieces in a square is
\(\frac{1}{3}\)
of the square.)
“How does the diagram show
\(\frac {6}{5}\)
?” (There are 6 pieces shaded and each one is
\(\frac{1}{5}\)
of the row.)
“How does the diagram show
\(\frac {6}{5} \times \frac {1}{3}\)
?” (There is
\(\frac{6}{5}\)
of a row shaded and that row is
\(\frac{1}{3}\)
of a square unit.)


correct_option_index: 4