: 1. Вычислите
1) -6 ⋅ 1,2 ⋅ (-5);
2) 0,4 ⋅ 19 - 25;
3) 1,25 ⋅ (-8) ⋅ (-0,5) ⋅ (-2);
4) 4,78 ⋅ (-4) ⋅ 25 + 500;
5) 5 ⋅ (-2,6) - 0,6 ⋅ (-100);
2. Упростите выражение и подчеркните его коэффициент:
1) -3,2 ⋅ 6x;
2) -0,8y ⋅ (-07);
3) 5а ⋅ (-1,4b) ⋅ 0,6c;
4) 1,5 ⋅ (-x) ⋅ 28 ⋅ y;
5) -3 c ⋅ 3,3 ⋅ b.
5. Упростите выражение -1,25c ⋅ 8d и найдите его значение, если c = -1,2 d =9.