Use the modulo node.

LevelNumber % 10 == 0

The % is the modulo operator, your modulo node. Take the level number, send it through the modulo node and check if the result is 0. If it is the number has a 0 at the end.

To explain how it works:

Remember back in primary when you was taught to divide for the first time you did not care about decimals? You were counting remainders.

```
10/4=2 and 2 as remainder.
```

Similarly the modulo and divide node are linked to this.

```
10/4 = 2
10%4 = 2
10/3 = 3
10%3 = 1
510/10 = 51
510%10 = 0
```

Hope this makes it easier to understand.