(7-1 5/12 ) : 6,7 + ( 5,75-3 1/6 ) : 15,5

[latex]( 7-1\frac{5}{12}) : 6,7 + ( 5,75-3 \frac{1}{6} ) : 15,5= \frac{226}{201}[/latex]  [latex]1) 7- 1 \frac{5}{12}=6 \frac{5}{12}[/latex] [latex]2) 6 \frac{5}{12}: \frac{67}{10}= \frac{77}{12} * \frac{10}{67}= \frac{770}{804} =\frac{385}{402} [/latex] [latex]3) \frac{575}{100} - \frac{19}{6} = \frac{3450-1900}{600} =\frac{1550}{600} [/latex] [latex]5) \frac{1}{6} + \frac{385}{402}= \frac{385+67}{402} = \frac{226}{201} [/latex] [latex]4) \frac{1550}{600}: \frac{155}{10} = \frac{1550}{600}* \frac{10}{155}= \frac{1}{6} [/latex]