few_shots: Example:
Problem/activity:
Problem 1
Solve using the standard algorithm. If you get stuck, use an area model and/or the partial products algorithm to help. Then assess the reasonableness of your answer.
a.
$$5,803\times46$$
b.
$$63\times2,116$$
Problem 2
Dunkin' introduced a croissant doughnut in 2014. In the first three months of its debut, they sold 7,870 dozen of them per day. How many croissant doughnuts were sold in the first three months?


Standard options: 
A. 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.
B. Find whole-number quotients of whole numbers with up to four-digit dividends and two-digit divisors, using strategies based on place value, the properties of operations, and/or the relationship between multiplication and division. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
C. Fluently multiply multi-digit whole numbers using the standard algorithm.


Your response:
C

Now, assign the following problem or activity to one or more relevant standards it aligns with.
shot_info: fl_problem_000674

5
options: Explain patterns in the number of zeros of the product when multiplying a number by powers of 10, and explain patterns in the placement of the decimal point when a decimal is multiplied or divided by a power of 10. Use whole-number exponents to denote powers of 10.

Read, write, and compare decimals to thousandths.

Use place value understanding to round decimals to any place.

Recognize that in a multi-digit number, a digit in one place represents 10 times as much as it represents in the place to its right and 1/10 of what it represents in the place to its left.
problem_activity: Narrative
The purpose of this activity is for students to make a reasonable estimate for a given product.
In addition to estimating the product, students also decide whether the estimate is too large or too small. In the activity synthesis, students consider about how far their estimate is from the actual product.
I
n the next activity, students will evaluate the expressions using a strategy of their choice.
Students choose between several different possible estimates and justify their choice before they calculate the product (MP3).
Engagement: Provide Access by Recruiting Interest.
Synthesis: Revisit math community norms to prepare students for the whole-class discussion.
Supports accessibility for: Social Emotional Functioning, Language
Launch
Groups of 2
Activity
5–7 minutes: independent work time
2–3 minutes: partner discussion
Monitor for students who:
relate the given expression to each proposed answer by rounding or changing one or both factors.
estimate by rounding the factors.
use benchmark numbers.
use place value reasoning or the properties of operations to explain why their estimate is reasonable.
Student Facing
Which estimate for the product
\(18 \times 149\)
is most reasonable? Explain or show your reasoning.
\(2,\!000\)
\(4,\!000\)
\(3,\!000\)
\(1,\!500\)
Are any of the estimates unreasonable? Explain or show your reasoning.
Do you think the actual product will be more or less than your estimate? Explain or show your reasoning.
Student Response
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Advancing Student Thinking
If students do not choose a reasonable estimate for
\(18 \times 149\)
, ask, “Can you explain how you chose your estimate?”
Activity Synthesis
Invite students to share their estimates for the product and their reasoning.
“Why do you think
\(3,\!000\)
is a good estimate?” (18 is close to 20 and 149 is very close to 150 and I know
\(20 \times 150 = 3,\!000\)
.)
“Is the value of
\(18 \times 149\)
greater than or less than
\(3,\!000\)
? How do you know?” (Less, because 18 is less than 20 and 149 is less than 150.)
“Can you estimate how much less?” (About 300, because I added 2 to 18 to get 20 and
\(2 \times 149\)
is about 300.)
Display:
\(18 \times 149\)
is about
\(2,\!700\)
.
“In the next activity, we’ll check to see how good our estimate is.”


correct_option_index: 0

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