I have a Price list as 

```
10
21
30
90
100
150
400

```

I want to add prices in 10 increments below 100. Above 100 to display in increments of 100

So my final price list would be like

```
10
20
30
40
50
60
70
80
90
100
200
300
400

```

Has anyone has done something similar to this. Any help or suggestions would be appreciated.

Thanks in advance