№8
1)делится на 5 без остатка: 35,90,550,350,40,25,105.
2)215:5=46 780:5=156 365:5=73
1080.
1)8*9/20 * 2/13 = 169/20 * 2/13 = 13/10=1*3/10
2)5*1/3 * 3/8 = 16/3 * 3/8= 2
3)10*1/2 * 2/7 =21/2 * 2/7 = 3
4)5/6 * 1*6/5= 5/6 * 11 / 5=11/6=1*5/6
5)3*19*3/8=28/9*3/8=4/3=1*1/3
6)9*1/7*3/4=64/7 * 3/4=48/7=6*6/7
7)10*1/5*10/17=51/5*10/17=3/2=1*1/2
8)3/11 * 5*1/2=3/11*11/2=3/2=1*1/2