Answer:27/220
Step-by-step explanation:
She must have 2 �1 coins and 1 50p coin.
She can choose the 2 �1 coins 3C2 = 3 ways.
For each of those 3 ways she can choose the
50p coin 9C1 or 9 ways.
That's 3�9=27 ways to get �2.50.
She can choose any 3 coins in 12C3 = 220 ways.
The desired probability is 27 ways out of
220 ways,or 27/220, or 13.5% of the time.
