1.2.4.5 реликт пжпхпхпхпх
1 - а) 2/5•1/7 = 2/35
б) 2•2/3•5/16 = 2/3•5/8 = 1/3•5/4 = 5/12
в) 3/4•2 = 3/2
2 - а) 7/9:4/5 = 7/9•5/4 = 35/36
б) 8:1•1/3 = 8/3