Grade 6 Mathematics · Unit 4: Understand and Use PercentagesStandard 6.AT.4

Lesson 4.34.3 Small Group · Group 1

Start hereWords, worked example, and sentence starters

Name Date Period

Learning target With my small group, I can estimate the percent of a number using benchmark percents, rounding, and compatible numbers — one step at a time, with support.

Start hereWords for this lesson

Read each word before you begin. Say it out loud.

Word	What it means	Example
estimateSpanish: estimación	A reasoned answer that is close enough to be useful, found without exact computation.	about 70% used
benchmark percentSpanish: porcentaje de referencia	A friendly percent — 1%, 10%, 25%, 50%, 75%, 100% — used as a landmark for estimating.	10%, 25%, 50%, 75%
compatible numbersSpanish: números compatibles	Numbers close to the originals that are easy to compute with mentally.	8.6% of 216 → 10% of 220: both nudged to numbers that divide nicely.
double number lineSpanish: recta numérica doble	Two parallel number lines that pair amounts with their percents at the same positions.	0, 30, 60 GB over 0%, 50%
the wholeSpanish: el todo	The quantity that counts as 100% in a problem — and it can change between questions.	all of the storage
DecomposeSpanish: Descomponer	Break a percent into friendly pieces that are easy to find.	15% = 10% + 5%

How it worksWorked exampleestimating a percent with benchmarks

These numbers are not on your problems. The steps are. Follow them with your own numbers.

A tablet holds 64 GB of storage and 47 GB are already used. About what percent of the tablet is full?

Name the whole: all 64 GB stands for one hundred percent.
Mark benchmarks: halfway is 32 GB, and three quarters of the way is 48 GB.
Locate the used amount, 47 GB — it sits right at the three-quarter mark.
Estimate with that benchmark, not with exact division.

Answer: About three quarters — roughly seventy-five percent — of the tablet is full.

Now you trySame steps, your turn

The steps are the same as the worked example. The numbers are yours. Do the work.

A water tank holds 80 L and has 22 L in it right now. About what percent of the tank is full?

The whole is L, and it stands for one hundred percent.
Half of the tank is L. One quarter of the tank is L.
The amount 22 L sits closest to which benchmark?
Estimate: about %

Answer:about what percent of the tank is full

Say it and write itSentence starters

Finish each sentence out loud with a partner. Then use them in your writing.

The whole in this problem is , so it stands for one hundred percent.
The benchmark closest to is .
My estimate is about % because .
I know my estimate is reasonable because .

Word bank estimateaboutbenchmarkwholepartdouble number linehalfone quarterthree quartersclose toreasonablecompare

Watch outA common mistake

Keeping the same whole for every question — when the problem says 'of the used storage,' the whole changes from 6 GB to 4 GB, and estimates anchored to the old whole are wrong before any arithmetic happens.

Grade 6 Mathematics · Unit 4: Understand and Use PercentagesStandard 6.AT.4

Lesson 4.34.3 Small Group · Group 1

Group 1Supported practice

Mastery check☐ Exceeds☐ Meets target☐ Needs practice

Name Date Period

Learning target With my small group, I can estimate the percent of a number using benchmark percents, rounding, and compatible numbers — one step at a time, with support.

1Complete each step, then write the final answer.
190 cans is 100%.
A class collected 189 cans. 9.5% of the cans were soup. About how many cans of soup is that?
1. 1Round 9.5% to a benchmark percent. What do you get?
2. 2Round 189 to a friendly number.
3. 3What do you divide 100% by to get 10%?
4. 4Divide 190 by 10 too. About how many cans of soup?
Final answer:
2Complete each step, then write the final answer.
320 students is 100%.
A school has 323 students. 26% of the students walk to school. About how many students walk?
1. 1Round 26% to a benchmark percent.
2. 2Round 323 to a number that is easy to divide by 4.
3. 3What do you divide 100% by to get 25%?
4. 4Divide 320 by 4 too. About how many students walk?
Final answer:
3Complete each step, then write the final answer.

Estimate 49% of 82.
Show your work
Hint 49% is close to 50%. Find half of a friendly number near 82.
Final answer:
4Complete each step, then write the final answer.

Estimate 10.4% of 587.
Show your work
Hint Round 10.4% to 10%. Round 587 to a friendly number. Then move the decimal point.
Final answer:
5Complete each step, then write the final answer.

Dad leaves a tip of 21% on a $29.80 meal. About how much is the tip?
Show your work
Hint Round 21% to 20% and $29.80 to $30. 100 ÷ 5 = 20, so divide $30 by 5.
Final answer:
6Circle the letter of the best answer. Show how you know.
Jay estimates 52% of 198 as about 200. Is his estimate reasonable?
1. ANo. 52% is about half, so it is about 100.
2. BYes. 198 is about 200.
3. CNo. It is about 52.
Hint 52% is close to which benchmark? What is that benchmark of 200?
Show your work

Explain your thinkingTo estimate 26% of 323, Kim used 25% of 320. Jo used 25% of 300. Are both estimates good? Explain.

Sentence starter I round 26% to ___ because ___. · Both estimates are close because ___.

How did it go? ☐ 4 · I can teach it☐ 3 · I've got it☐ 2 · I need a hint☐ 1 · I need help