$$\frac{120 + 140 + 126 + 114 + 110}{5} = \ \frac{610}{5} = 122\backslash n$$

Zadanie 2

$$\frac{70 + 60 + 58 + 62 + 75 + 65}{6} = \ \frac{390}{6} = 65$$

Zadanie3

$\frac{1400 + 1800 + 2200 + 2600\ }{4} = \ \frac{8000}{4}$ = 2000