1) (27,527 + 7,983) – 7,527 = 27,527 – 7,527 + 7,983 = 20 + 7,983 = 27,983;
2) 14,49 – 3,1 – 5,49 = 14,49 – 5,49 – 3,1 = 9 – 3,1 = 5,9;
3) 14,1 – 3,58 – 4,42 = 14,1 – (3,58 + 4,42) = 14,1 – 8 = 6,1;
4) 4,142 – (2,142 + 1,9) = 4,142 – 2,142 – 1,9 = 2 – 1,9 = 0,1.