Ratio and proportion

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?
problem

Zin Obelisk

Age

11 to 14

Challenge level

2 out of 3

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.