Probability Scale

• A probability scale runs from ‘impossible’ to ‘certain’.

• You will be asked to place certain events on the scale, depending on how likely they are to happen.

• I will live to be 300.
  • It's impossible to live to be 300. So you would place A at the impossible end of the scale.

• Thursday follows Wednesday.
  • Thursday always follows Wednesday. So you would place 'B' at the certain end of the scale.

I will win £500,000 tomorrow.

• There's a very small chance you could win £500,000 tomorrow, but it's very unlikely. So you would place C very near the impossible end of the scale.

• I will flip a coin and it will land on tails.
  • There are 2 sides to a coin - heads and tails. So there is an even chance of this happening.