Need Help With Math

Question

Dairy Queen has four different sizes for their Blizzards. There are twenty types of Blizzards. How many different Blizzards can be ordered if you were to get one with one of five extras?

Answer 1

There are 4 different sizes of 20 types of Blizzards:

Let a number be a type of Blizzard and a letter be the size.

A1, A2, A3, ..., A20

B1, B2, B3, ..., B20

C1,C2, C3, ..., C20

D1,D2, D3, ..., D20

Here, the type and the size matter.

i.e.

A1 and B1 are different even if they have the same size

A1 and A2 are different even if they have the same type.

(4)(20) = 80 different Blizzards.

You have to get also one of the 5 extras.

(80)(5) = 400 ways can be ordered