10-0,9

Likely interpretation: 10 − 0,9 (decimal comma) = 10 − 0.9 = 9,1 (or 9.1 in decimal point notation).

Quick steps:

• 0,9 = 9/10
• 10 − 9/10 = 100/10 − 9/10 = 91/10 = 9,1

If you meant something else, tell me and I’ll adjust. Want a few similar practice problems?