These worksheets are free forever. Want lessons that adapt to your child as they learn, plus progress tracking? Try Ignition Learning free.
Sign up freeIgnition Learning — Activity Sheet
Mathematics · Year 9
A rate compares two different quantities with different units, like km/h or $/kg. A unit rate expresses this per single unit (e.g. "cost per item"), making comparisons easy. Direct proportion means two quantities increase or decrease together at a constant rate — if you double one, the other doubles too, like the relationship between distance, speed and time (distance = speed × time).
Example
A car travels 240km in 3 hours — that's a rate of 240 ÷ 3 = 80km/h. At that same speed, travelling for 5 hours would cover 80 × 5 = 400km — the distance and time are directly proportional at a constant speed.
Key terms
Questions
1. A rate compares:
2. Km/h is an example of a:
3. A car travels 100km in 2 hours. What is its speed?
4. Distance = Speed ×:
5. A unit rate expresses a rate:
6. 6 apples cost $3. What is the unit rate (cost per apple)?
7. Direct proportion means two quantities:
8. A car travels 240km in 3 hours. What is its speed?
9. At 80km/h, how far would a car travel in 5 hours?
10. 4kg of apples costs $12. What is the cost per kg?
11. If 3 items cost $18, how much would 5 items cost at the same rate?
12. A tap fills a 60L tub in 12 minutes. What is the fill rate per minute?
13. If two quantities are directly proportional and one doubles, the other:
14. A recipe for 4 people uses 200g of rice. How much rice for 10 people, at the same rate?
15. A car uses 40L of fuel to travel 480km. At the same rate, how far could it travel on 25L?
16. Worker A paints a fence in 6 hours; Worker B paints an identical fence in 4 hours. Working together at their individual rates, are they faster or slower than either alone?
17. A photocopier prints 45 pages in 3 minutes. How many pages could it print in 8 minutes at the same rate?
18. Two cars leave the same point, one at 60km/h and one at 80km/h, travelling in the same direction. After 3 hours, how far apart are they?
19. A 500g bag of flour costs $2.50, and a 750g bag costs $3.30. Which is the better value per gram?
20. A hose fills a pool at 25L per minute. How long will it take to fill a 3,000L pool?
21. If y is directly proportional to x, and y = 12 when x = 4, what is y when x = 10?
Answer key (parent copy)