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Maths I

Ratio

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Writing a comparison in the form of a ratio

Example

A farmer has 3 cats and 7 dogs. Write down the ratio of

A dog and a cat look at each other.
  • cats to dogs.

  • dogs to cats.

 

  • cats : dogs.

    3 : 7

  • dogs : cats.

    7 : 3

Now try this question:

Question

The same farmer also has 85 sheep and 15 cows. Write down the ratio of cows to sheep in its simplest form.

Answer
  • cows : sheep = 15 : 85

  • 15 and 85 are both divisible by 5

  •  

  • {15 \over 5} = 3

  •  

  • {85 \over 5} = 17

  •  

  • So 15 : 85

  • = 3 : 17

A ratio is used to compare two quantities which are measured in the same units.

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Watch

A stunt accident being set up for an episode of Casualty.

Class Clips

Video clip about the use of maths, including ratio, in setting up a crash stunt for Casualty

Play

A picture of Mia Cadaver

Tombstone Timeout

Swot up your sums with Mia Cadaver's maths game

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