1.3целых1/4+6,4-7,5=? 2.2/11*(14целых1/3+2целых1/6)=? 3.16,5: 2,75-1/19*57=? 30 !

1.
3 1/4 + 6,4 - 7,5 = 13/4 - 1,1 = 13/4 - 11/10 = 65/20 - 22/20 = 43/20 = 2ц 3/20,
2.
2/11 * (14 1/3 + 2 1/6) = 2/11 * (43/3 + 13/6) = 2/11 * (86/6 + 13/6) = 2/11 * 99/6 = 3,
3.
16,5 : 2,75 - 1/19 * 57 = 6 - 3 = 3,