28 · 3 – 57 = 84 – 57 = 27
34 + 13 · 5 = 34 + 65 = 99
98 – 23 · 4 + 24 = 98 – 92 + 24 = 6 + 24 = 30
28 · 2 – 13 · 4 = 56 – 52 = 4
(49 + 28) : 7 = 77 : 7 = 11
(64 + 24) : 4 = 88 : 4 = 22
Ответ: 1) 27; 2) 99; 3) 30; 4) 4; 5) 11; 6) 22.