Hello everyone, i should rly need some help with my excel-work.

Atm, my problem is that i´ve made a funtion with "Round off" that makes the significans be "5" all the time. But the problem is that when the mesure reaches over 80 i need it to "round off" at even 10mm, like 90, 100, 110 etc instead of 85,90,95...

If anyone got a sollution to this problem, please help me

Thanks in advance