10. (Устно.) (54 - 19 - 24 - 19) : 5 100 – (78 · 13 – 39 · 24)

1. (54 - 19 - 24 - 19) : 5 = (54 - (19 + 19) - 24) : 5 = (54 - 38 - 24) : 5 = (54 - 62) : 5 = -8:5 = -1,6
2. 100 – (78 ⋅ 13 – 39 ⋅ 24) = 100 – (78 ⋅ 13 – 39 ⋅ 2 ⋅ 12) = 100 – (78 ⋅ 13 – 78 ⋅ 12) = 100 – 78 ⋅ (13 – 12) = 100 – 78 ⋅ 1 = 100 – 78 = 22

Ответ: -1,6; 22