Question

A key code must contain 4 letters and 3 numbers. The letters may be any letter of the alphabet. The numbers should be any number from 0 to 5. How many different key code combinations are there?

Answer 1

i believe its 624
hope this helps:)

Answer 2

We can choose any 4 of 26 letters

And we can choose any 3 of 6 numbers

And we have 7! arrangements of these letters and numbers

So we have

C(26,4)* C(6,3) *7! = 1,506,960,000 combinations