б) (2*7)*5 10*7
---------=---------
(7*3)*3 9*7
в) (7*6)*43 258*7
---------=-----------
(7*5)*5 25*7
г) (9*7)*13 117*7
----------=----------
(4*7)*40 160*7
1/3=0,3;
2/5=0,4;
3/4=0,76;
1/7=0,14285;
5/8=0,625;
4/9=0,44;
3/10=0,3;
5/6=0,833;
7/11=0.6363;
9/20=0,45
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