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Teaching video
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Grade 4 chapters and video availability01 · Read and understand
What you will learn
- List whole-number factor pairs systematically.
- Explain your method and check what the result means in the stated situation.
Before you start
Multiplication and division facts, simple fractions, place value, and basic length and area measurement.
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
Find all positive whole-number factor pairs of 24.
Why this math matters
List every possible whole-number rectangle dimension for a fixed unit-square area. 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.
Find every factor pair
PausedQuestion: Start with the question. Paused.
Question
Start with the question
Find all positive whole-number factor pairs of 24.
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
1×24, 2×12, 3×8
Test possible smaller factors in order.
Connect the parts
4×6; 5 does not divide 24
Stop after passing the square-root boundary without repeating pairs.
State and check the result
Pairs: (1,24), (2,12), (3,8), (4,6)
Reversing a listed pair adds no new pair of dimensions.
The result
Pairs: (1,24), (2,12), (3,8), (4,6)
Reversing a listed pair adds no new pair of dimensions.
Common mistakes to catch
- A factor divides exactly into the number.
- Systematic searching avoids omitted or duplicated pairs.
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
List factor pairs of 18.
Show a hint
Try possible smaller factors through four.
Reveal answer and explanation
(1,18), (2,9), (3,6)
Four does not divide eighteen; later pairs reverse earlier ones.
Practice 2
Is 5 a factor of 24?
Show a hint
A factor must divide with no remainder.
Reveal answer and explanation
No
24 ÷ 5 leaves remainder four.
Take the idea with you
List every possible whole-number rectangle dimension for a fixed unit-square area.
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: Find when repeating schedules meet
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