Direct proportion
The Maths Habit
3 pens cost one bag of coins. Which is a fair price for 6 pens?
Share the money equally. How much is in each part?
- Direct proportion
- When one amount is multiplied, the other amount is multiplied by the same number.
- Equal parts
- Parts that are all the same size.
- Total
- All the parts added together.
- 1Cut the bar.One part for each thing.
- 2Find one part.Divide the total by the number of parts.
5 tickets cost £20. How much does 1 ticket cost?
3 cakes cost £15. How much does 1 cake cost?
5 tickets cost £20. How much does 1 ticket cost?
4 pens cost £8. How much does 1 pen cost?
5 tickets cost £20. How much does 1 ticket cost?
10 stamps cost £30. How much does 1 stamp cost?
5 tickets cost £20. How much does 1 ticket cost?
2 hats cost £18. How much does 1 hat cost?
15 mugs cost £30. How much does 1 mug cost?
24 bags cost £16. How much does 1 bag cost?
310 cards cost £50. How much does 1 card cost?
43 kites cost £21. How much does 1 kite cost?
Each part is worth the same. What is the total?
- 1Cut the bar.One part for each thing.
- 2Find one part.Divide the total by the number of parts.
- 3Multiply.Cut a new bar. Multiply one part by the new number of parts.
4 pens cost £12. How much do 7 pens cost?
2 cakes cost £10. How much do 5 cakes cost?
4 pens cost £12. How much do 7 pens cost?
5 tickets cost £10. How much do 3 tickets cost?
4 pens cost £12. How much do 7 pens cost?
3 books cost £15. How much do 4 books cost?
4 pens cost £12. How much do 7 pens cost?
2 bags of rice weigh 6 kg. How much do 5 bags weigh?
Answer sheet
Is it right?
Thumbs up: right. Thumbs down: wrong.
3 pens cost £6, so 6 pens cost £12
Right2 cakes cost £4, so 5 cakes cost £7
Wrong: find one part, do not add on4 mugs cost £20, so 1 mug costs £5
Right5 cards cost £10, so 1 card costs £50
Wrong: divide, do not multiply3 hats cost £9, so 4 hats cost £12
Right
6 pens cost £4.20. How much do 4 pens cost?
£2.80A recipe for 10 flapjacks uses 250 g of oats. How many grams of oats are needed for 25 flapjacks?
625 gShop A sells 3 cakes for £6.60. Shop B sells 5 cakes for £10.50. Which shop is cheaper for one cake?
Shop B
3 cakes cost £12. How much do 5 cakes cost?
£204 pens cost £20. How much do 6 pens cost?
£305 tickets cost £35. How much do 2 tickets cost?
£14