91,7:7

If ":" is division and "," is the decimal separator (European notation):

• 91,7 ÷ 7 = 13,1

Explanation: 91.7 / 7 = 13.1, so in decimal comma form it is 13,1.

If you meant the ratio 91,7:7, it simplifies to 13,1 : 1 (i.e., 13.1 to 1). Would you like the steps shown differently or in fractional form?