Hello Some_One
You're doing a great job! I agree with all your answers.
Grandad
I am just wondering if I did these questions correctly as I do not have an answer key for them.
A second opinion would be greatly appreciated. Thanks.
A pizza company has 15 toppings to choose from, of which 6 are vegetables.
1. How many different three-topping pizzas have exactly one vegetable topping?
= (all possible combinations of 1 veggie topping) x (all possible combinations of 2 non-veggie toppings)
= x
= 216
2. How many different three-topping pizzas have at least one vegetable topping?
= (all possible combinations of 3-topping pizzas) - (pizzas without any veggies)
= -
= 371
3. How many different three-topping pizzas have exactly two vegetable toppings?
= (all possible combinations of 2 veggie toppings) x (all possible combinations of 1 non-veggie topping)
= x
= 135
4. How many different three-topping pizzas have at least two vegetable toppings?
= (all possible combinations of 3-topping pizzas) - (pizzas without any veggies) - (pizzas with exactly 1 veggie)
= - - ( x )
= 455 - 84 - 216
= 155
OR
= (pizzas with exactly 2 veggies) + (pizzas with exactly 3 toppings)
= ( x ) +
= 135 + 20
= 155