38/7 - (5/2 + 4/3): (1/6)=
=38/7 - (15/6 - 8/6):(1/6)=
=38/7 - (23*6)/6=
38/7 - 23 = (38 - 23*7)/7 = (38 - 161)/7 = - 123/7 = - 17 4/7
<span>ср ар=(20+21+22+24+26+28)/2=70,5
мед=(22+24)/2=23
70,5+23=93,5</span>
6/100*х=х/100*6
3/50*х=х*3/50
х=х
у/100*8=8/100*у
у=у