Question

Pita has 12 coins in her bag there are three 1 pound coins and nine 50p coins she takes 3 coins out of the bag at random, work out the probability she takes out exactly £2.50

Answer 1

The probability of taking out a £1 coin is 3/12 or 1/4 and the probability of taking out 50p is 9/12 or 3/4.

The only way for her to take out £2.50 with 3 coins is to pull out 2 £1 coins and 1 50p coin.

Now we have to multiply the probability of each individual coin being taken out together. This will be 1/4 x 1/4 x 3/4 which equals 3/64.

The probability is 3/64