Grade 6 · Ratios
Robot controller: Build equivalent batches
Robot controller investigation: build equivalent batches. Change the quantities, follow the motion, and explain the result using the displayed mathematical relationship.
Predict what will happen, press Play, then pause and explain what changed. Every control also works without playback.
Watch the relationship
PausedHD animation studio
From experiment to screen.
Present a crisp Canvas scene, save a full-HD image, or capture your model as a silent video.
Understand what you are seeing
The idea behind the motion.
Equivalent ratios multiply both quantities by the same factor. Building complete copies makes that requirement visible: multiplying just one quantity changes the mixture. A part-to-part ratio is different from either part as a fraction of the combined total. This investigation begins with first quantity per batch = 2; second quantity per batch = 3; final complete batches = 2. Treat the named setting as a constructed classroom model, then explain which relationships would still hold if its numbers changed.
A relationship to keep
a : b = ka : kb
Read the symbols alongside the explanation. A diagram shows the relationship; the assumptions tell you when it applies.
- STEP 1
Represent the given quantities
Read the two quantities in one complete batch and preserve their order when naming the ratio.
- STEP 2
Follow the changing model
Watch whole batches appear. Each copy contributes the same a and b, so both cumulative amounts grow together.
- STEP 3
Check and explain the relationship
Divide the two totals to check the unchanged ratio; use a+b as the denominator only when asking for a share of the whole.
Your turn to explain
Make a prediction. Test your reasoning.
Robot controller: A batch uses 2 units of the first ingredient and 3 of the second. Find both totals for 2 batches.
Use the values specified in the question. Reset restores the initial values for this investigation.
Compare your explanation
4 and 6 units; dividing the totals gives the original ratio 2:3.
Work through a full lesson
Connect the animation to a worked example and practice questions.