There are many baubles stored in a large storage box in the loft.
The baubles are red, green, gold or silver.
A bauble is chosen at random from the storage box.
The probability of getting each of the colours is:
Red = 0.3
Green = 0.1
Gold = 0.35
Silver = 0.25
In the box there are 20 silver baubles.
How many red baubles are there?
Answer
If the probability of getting a silver bauble is 0.25 and the number of silver baubles is 20 then the total number of baubles is 20/0.25 or 80.
Then multiply 80 by 0.3 to find the number of red baubles.
Number of red baubles = 24