Learn with Amar
Teaching video
A teaching recording for this chapter has not been published yet. Start with the worked example below and explore the related animations where available.
Grade 3 chapters and video availability01 · Read and understand
What you will learn
- Organize choices so no combination is missed or repeated.
- 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
A bookmark can be red or blue, with a star, heart, or circle. How many different color-shape combinations?
Why this math matters
Use a table or tree to plan all allowed design combinations. 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.
List every simple combination
PausedQuestion: Start with the question. Paused.
Question
Start with the question
A bookmark can be red or blue, with a star, heart, or circle. How many different color-shape combinations?
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
Red: star, heart, circle
Keep one color fixed while using all shapes.
Connect the parts
Blue: star, heart, circle
Repeat the complete shape list for the other color.
State and check the result
2 × 3 = 6 combinations
Each listed pair has one color and one shape.
The result
2 × 3 = 6 combinations
Each listed pair has one color and one shape.
Common mistakes to catch
- Adding the numbers of choices does not count pairs.
- The multiplication rule here assumes every first choice allows every second choice.
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
Three shirt colors and two hat colors make how many outfits?
Show a hint
Pair each shirt with both hats.
Reveal answer and explanation
6
3 × 2 = 6 combinations.
Practice 2
Why is red-star not listed again when moving to blue?
Show a hint
A combination is determined by both labels.
Reveal answer and explanation
It was already counted and is not blue
Organized lists separate choices by category and avoid duplicates.
Take the idea with you
Use a table or tree to plan all allowed design combinations.
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.
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