А) 12 21 13 31 14 41 15 51 16 61 17 71 18 81 19 91
23 24 25 26 27 28 29 21 32 31 34 35 36 37 38 39 41 42 43 44 45 46 47 48 49 51 52 53 54 55 56 57 58 59 61 61 63 64 65 66 67 68 69
<span>4788 = 2*2*3*3*133
.......................................................</span>
А) ...-40 =258, ...-400 = 256, ...- 70 = 40, ...-60 = 180
б) 370-...=50, 150-...=70, 680-... = 110, 290-... = 120
в) ...+80 = 170, ...+300 = 572, 150+... = 990, 130+... = 60