1)у-5/12=3/10
У=3/10+5/12
У=18/60+25/60
У=43/60
2)4/15+у=11/25
У=11/25-4/15
У=33/75-20/75
У=13/75
1. 987-567 = 420
2. 420: 6 = 70
3. 70- 35 = 35