7 = (7·8)/8 = 56/8 7 и 5/8 = 56/8 и 5/8
9 = (9·4)/4 = 36/4 9 и 1/4 = 36/4 и 1/4
4 = (4·7)/7 = 28/7 3/7 и 4 = 3/7 и 28/7
8 = (8·10)/10 = 80/10 9/10 и 8 = 9/10 и 80/10
15 = (15·10)/10 = 150/10 15 и 3/10 = 150/10 и 3/10
20 = (20·8)/8 = 160/8 20 и 3/8 = 160/8 и 3/8
9 = (9·12)/12 = 108/12 9 и 5/12 = 108/12 и 5/12
3 = (3·11)/11 = 33/11 7/11 и 3 = 7/11 и 33/11
4 надо, у меня всё))))))))))
(4/5-3/4)*7,8+(2/3+4/7)*7/13;
1)4/5-3/4=16/20-15/20=1/20=0,05; ///
2)2/3+4/7=14/21+12/21=26/21; ///
3)0,05*7,8=0,39; 1/20*39/5=39/100;///
4)26/21*7/13=2/3; ///
5)39/100+2/3=117/300+200/300=317/300=3 цел17/300