Ratio and proportion

problem

Nutty Mixture

Age

7 to 11

Challenge level

Use the ratio of cashew nuts to peanuts to find out how many peanuts Rachel has. What would the ratio be if Rachel and Marianne mixed their bags?
problem

Number the Sides

Age

7 to 11

Challenge level

The triangles in these sets are similar - can you work out the lengths of the sides which have question marks?
problem

Rod Ratios

Age

7 to 11

Challenge level

Use the Cuisenaire rods environment to investigate ratio. Can you find pairs of rods in the ratio 3:2?
problem

Retiring to Paradise

Age

11 to 14

Challenge level

When Charlie retires, he's looking forward to the quiet life, whereas Alison wants a busy and exciting retirement. Can you advise them on where they should go?
problem

Tray Bake

Age

11 to 14

Challenge level

My recipe is for 12 cakes - how do I change it if I want to make a different number of cakes?
problem

Toad in the Hole

Age

11 to 14

Challenge level

Is it cheaper to cook a meal from scratch or to buy a ready meal? What difference does the number of people you're cooking for make?
problem

Straw Scaffold

Age

11 to 14

Challenge level

Build a scaffold out of drinking-straws to support a cup of water
problem

Zin Obelisk

Age

11 to 14

Challenge level

In the ancient city of Atlantis a solid rectangular object called a Zin was built in honour of the goddess Tina. Your task is to determine on which day of the week the obelisk was completed.
problem

Washing Elephants

Age

11 to 14

Challenge level

How long will it take Mary and Nigel to wash an elephant if they work together?
problem

Do Unto Caesar

Age

11 to 14

Challenge level

At the beginning of the night three poker players; Alan, Bernie and Craig had money in the ratios 7 : 6 : 5. At the end of the night the ratio was 6 : 5 : 4. One of them won $1 200. What were the assets of the players at the beginning of the evening?