1)= 106+8,2*25/41 = 106+41/5*25/41= 106+5 = 111

2)= 1+ 0,85* 16/17= 1+17/20*16/17= 1 + 1/5 *4 = 1 +4/5= 9/5=1,8

3)=55/81*44/135+8 11/12 = 55/81 * 135/44 +107/12 = 5/3 * 5/4 + 107/12= 25/12 + 107/12 = 11

4)= 2 2/7 - 303/400 : 707/800 = 16/7 - 303/400 * 800/707 = 16/7 - 3 *2/7 = 16/7-6/7 = 10/7 = 1 3/7