Compound Units
Use compound units such as speed (distance ÷ time), unit pricing (cost ÷ quantity), and density (mass ÷ volume); solve problems involving compound units
Lesson
Set out your lesson
“A compound unit combines two measurements, such as km/h, dollars per item, or grams per millilitre. Divide the first quantity by the second and keep both units.”
Bring to the table
- Paper
- Pencil
- Calculator if useful
Extra for the adult
Worked example. 36 km in 2 h gives 18 km/h: 18 kilometres for each hour at that average rate.
Optional challenge. Create a metric compound-unit example and explain why the base units must match for a fair comparison.
What to notice. Photo of calculations with units or parent note recording speed, better unit price, density, and explanations.
Share and support
Family records and proof options
Keep a record of your learning
Save photos, notes, and attendance. Export a proof packet for compliance or portfolio reviews.
Learning resources
Extra practice links — they do not replace Gakuva’s teaching approach.
PhET Interactive Simulations · Practice link — not the full lesson
Proportion Playground
Before you open · source notes
Proportion Playground supports hands-on exploration for Compound Units. Not every lab worksheet.
Free interactive page, no sign-in required for the tested path.
Before you openAsk the learner what they changed in the sim or page and what they observed.
Opening this link does not save learning or assess mastery.
Source, access and review notes
Public PhET Interactive Simulations page. An anonymous GET on 2026-11-12 returned HTTP 200 with no login or payment prompt for this URL. Opening the link does not save practice or assess mastery. An adult should preview and guide the learner.
PhET Interactive Simulations. “Proportion Playground.” External page; Gakuva does not copy, host, embed, or redistribute materials.
Unknown — link only
Check understanding
- Calculate average speed given distance and time, converting between km/h and m/s if needed
- Compare unit prices of two products sold in different quantities to find the better deal
- Use the density formula to find mass, volume, or density given the other two values
“If a car travels 150 miles in 2.5 hours, can your child work out its average speed — and use the same idea to solve problems about price per kilogram or density of a material?”
Curriculum record
- Type
- Procedural
- Subject
- Mathematics
- Domain
- Ratio & Proportion
- Age range
- Ages 11–14
Standards