22,2: 5 2\7-2 3/5= (7 1/4-6 7/18)*7,2+2,8=

22 2/10:5 2/7=222/10:37/7=222/10*7/37=6/10*7/1=42/10=4,2
4,2-2 3/5=42/10-13/5=42/10-26/10=16/10=1,6

7 1/4-6 7/18=7-6+1/4-7/18=1+9/36-14/36=1+(-5/36)=36/36-5/36=31/36
31/36*7,2=31/36*72/10=31/1*2/10=62/10=6,2
6,2+2,8=9