Learn with Amar
Teaching video
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Grade 3 chapters and video availability01 · Read and understand
What you will learn
- Compare a number's distance to adjacent hundreds.
- Explain your method and check what the result means in the stated situation.
Before you start
Place value through hundreds, addition and subtraction, equal groups, and equal shares.
Keep paper nearby. Read the question once for the context, then again to identify what is known and what you need to find.
Start with a question
Round 648 to the nearest hundred.
Why this math matters
Estimate a large count at a level of precision suited to the question. The worked example shows how to connect the situation, its mathematical representation, and a check on the result.
Set up the model
A useful answer starts with clear assumptions:
- Use the units, grouping rules, and reference whole stated in the question.
- Treat the supplied counts and measurements as exact within the classroom model, unless an estimate or a random outcome is requested.
02 · Work through the example
Follow the reasoning, one step at a time.
Try to predict the next step before reading it. After each calculation, explain why the operation makes sense and how it helps answer the original question.
Work through it with Amar
See this example unfold.
The complete worked example, one idea at a time.
Round to the nearest hundred
PausedQuestion: Start with the question. Paused.
Question
Start with the question
Round 648 to the nearest hundred.
Before you calculate
Read what is known and what you need to find. Make a prediction before moving to the first calculation.
Starts paused. Play advances through the full text at a reading pace; pause whenever you need more time. Previous, Next, and the phase buttons let you set your own pace. Playback pauses when this walkthrough leaves the screen or you switch tabs.
Your device’s reduced-motion setting keeps each phase still. Manual controls remain available. The full written solution stays below.
Represent the situation
Neighboring hundreds: 600 and 700
Find the lower and upper multiples of one hundred.
Connect the parts
648 − 600 = 48; 700 − 648 = 52
Compare the two distances.
State and check the result
648 rounds to 600
It is four units closer to six hundred than seven hundred.
The result
648 rounds to 600
It is four units closer to six hundred than seven hundred.
Common mistakes to catch
- The rounding place determines allowable rounded values.
- Use a declared halfway rule; here halfway rounds upward.
03 · Practice independently
Try it before revealing the answer.
Use paper or a calculator as needed. Write your units and reasoning, then open the hint or explanation to check your approach.
Practice 1
Round 872 to the nearest hundred.
Show a hint
Compare eight hundred and nine hundred.
Reveal answer and explanation
900
It is twenty-eight from nine hundred and seventy-two from eight hundred.
Practice 2
Can 649 round to 650 to the nearest hundred?
Show a hint
The result must be a multiple of one hundred.
Reveal answer and explanation
No; it rounds to 600
650 is a multiple of ten, not a hundred.
Take the idea with you
Estimate a large count at a level of precision suited to the question.
04 · Reflect and continue
Can you explain it in your own words?
Before moving on, explain the main idea without looking at the worked example. Try both practice questions, check your reasoning, and name one mistake you now know how to avoid. Return to a step if you still need support.
Up next: Multiply a one-digit number by tens
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