# A whole number consists of the 2 4, 6, 8, and 0. How many whole numbers are possible?

##### 1 Answer

321 using a single copy of each number.

#### Explanation:

A whole number is a number that sits within the range

We can make whole numbers using one, some, or all of the numbers listed. **I'm going to assume that we can only use a single copy of each number, so the number #24# is ok but numbers #22# and #44# are not.** So let's see what we can make.

Before we start, I'm noticing that if we make a 2-digit number starting with

1-digit = 1

For 2-digit numbers, we have a permutation of five numbers, select 2:

For 3-digit numbers, we do the same for five numbers, pick three:

For 4-digit numbers, we do the same for five numbers, pick four:

And now we do the 5-digit numbers:

And now we add them up: