3.318 Вычислите.

а) 90 - 16 = 74; 74 : 2 = 37; 37 + 23 = 60; 60 : 5 = 12. б) 50 + 19 = 69; 69 : 3 = 23; 23 + 47 = 70; 70 : 5 = 14. в) 42 + 26 = 68; 68 : 2 = 34; 34 - 16 = 18; 18 : 3 = 6. г) 60 - 22 = 38; 38 : 2 = 19; 19 + 46 = 65; 65 : 5 = 13. д) 70 - 19 = 51; 51 : 3 = 17; 17 + 13 = 30; 30 : 5 = 6.