Ratio and proportion

problem

Nutty Mixture

Age

7 to 11

Challenge level

2 out of 3

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

2 out of 3

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

3 out of 3

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

Racing Odds

Age

11 to 14

Challenge level

1 out of 3

In a race the odds are: 2 to 1 against the rhinoceros winning and 3 to 2 against the hippopotamus winning. What are the odds against the elephant winning if the race is fair?
problem

Retiring to Paradise

Age

11 to 14

Challenge level

1 out of 3

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

1 out of 3

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

1 out of 3

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

1 out of 3

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

Off the Cuff

Age

11 to 14

Challenge level

2 out of 3

Can you work out the ratio of shirt types made by a factory, if you know the ratio of button types used?
problem

Double Cover

Age

11 to 14

Challenge level

2 out of 3

Weekly Problem 3 - 2007
What is the ratio of the area of the table covered twice, to the uncovered area?