few_shots: 
Example:
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: 
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.

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.

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_pos_0

6
standard_description: Understand that the three digits of a three-digit number represent amounts of hundreds, tens, and ones; e.g., 706 equals 7 hundreds, 0 tens, and 6 ones. Understand the following as special cases:
- 100 can be thought of as a bundle of ten tens — called a “hundred.”
- The numbers 100, 200, 300, 400, 500, 600, 700, 800, 900 refer to one, two, three, four, five, six, seven, eight, or nine hundreds (and 0 tens and 0 ones).
problem_activity: Narrative
This Number Talk encourages students to think about the strategies they can use to multiply 2 two-digit numbers. Students can decompose factors by place value to multiply by multiples of ten, or they can use a doubling and halving strategy to create an equivalent expression. The strategies elicited here will be helpful later in developing a flexible sense of numbers and using this sense to make decisions when multiplying mentally.
Launch
Display one expression.
“Give me a signal when you have an answer and can explain how you got it.”
1 minute: quiet think time
Activity
Record answers and strategy.
Keep expressions and work displayed.
Repeat with each expression.
Student Facing
Find the value of each expression mentally.
\(30 \times 7\)
\(15 \times 14\)
\(50 \times 8\)
\(25 \times 16\)
Student Response
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Activity Synthesis
“How can
\(30 \times 7\)
help you solve
\(15 \times 14\)
?” (
\(30 \times 7\)
is twice as many groups with half as much in each group, which results in the same product with easier factors to multiply mentally.)


aligns: no