A pizza restaurant is offering a special price on pizzas with
2
22 toppings. They offer the toppings below:
Pepperoni
Sausage
Ham
Chicken
Green pepper
Onion
Mushroom
Pineapple
Pepperoni
Chicken
Mushroom


Sausage
Green pepper
Pineapple


Ham
Onion




Suppose that Rosa's favorite is sausage and onion, but her mom can't remember that, and she is going to randomly choose
2
22 different toppings.
What is the probability that Rosa's mom chooses sausage and onion?