Первый пример
1) -3 1/3×1,9=- 3 1/3 × 1 9/10 = - 10/3 × 19/10 = - 19/3 = - 6 1/3
2) 19,5÷4 1/3=19 5/10 ÷ 4 1/3 = 39/2 ÷ 13/3 = 39/2 × 3/13 = 9/2 = 4 1/2
3)- 6 1/3 + 4 1/2 = - 19/3 + 9/2 =(-19 × 2 + 9 × 3)/6 = -38/6 + 27/6 = - 11/6 = - 1 5/6
4)0,16-62/75=6/100 - 62/75 = 4/25 - 62/75 = (4 × 3 - 62 × 1)/75 = 12/75 - 62/75 = - 50/75 = - 2/3
5)-1 5/6÷(-2/3)=- 11/6) ÷ ( - 2/3) = - 11/6 × ( - 3/2) = 11/4 = 2 3/4
Ответ: 2 3/4 или 2,75
второй пример
1) -2 2/11×4,125= - 2 2/11 × 4 125/1000 = - 24/11 × 33/8 = - 9
2)1,6×3 3/4=1 6/10 × 3 3/4 = 8/5 × 15/4 = 6
3)-9+6= - 3
4)5 5/6 × 2 4/7 = 35/6 × 18/7 = 15
5)9-15= - 6
6) -3÷(-6)=0,5
ответ:0,5