5 2/3 + 9 4/6

2/3 + 4/6

../6 + 4/6

4/6 + 4/6

8/6

(8 ÷ 2)/(6 ÷ 2)

4/3

= 1 1/3

5 + 9 + 1

14 + 1

= 15

= 15 1/3

5,12 + 12,7 - 1,6

(5 + 12),(12 + 7) - 1,6

17,19 - 1,6

(17 - 1),(19 - 6)

= 16,13

10!! - 5! + 7!!!

(10 × 8 × 6 × 4 × 2) - (5 × 4 × 3 × 2) + (7 × 4)

(80 × 6 × 4 × 2) - (20 × 3 × 2) + 28

(480 × 4 × 2) - (60 × 2) + 28

(1.920 × 2) - 120 + 28

3.840 - 120 + 28

3.720 + 28

= 3.748

f(x) = 5x + x! - x³

f(8) = 5(8) + 8! - 8³

f(8) = (5 × 8) + (8 × 7 × 6 × 5 × 4 × 3 × 2) - 8³

f(8) = 40 + (56 × 6 × 5 × 4 × 3 × 2) - 8³

f(8) = 40 + (336 × 5!) - (8 × 8 × 8)

f(8) = 40 + (336 × 120) - (64 × 8)

f(8) = 40 + 40.320 - 512

f(8) = 40.360 - 512

f(8) = 39.848

25 - (14 - 8) + 67

25 - 6 + 67

19 + 67

= 86