1- 5/6, 5/6, 3/2
2- 3/16<5/24; 13/330<9/220
3 a7/8-5/6=21/24-20/24=1/24
b13/16+7/24=39/48+14/48=53/48
c- 19/20-5/12+9/5=57/60-25/60+108/60=140/60
Угол ABD = 70 * , Угол BDC = 30 *
12+3:3=13
т.к сначала деление, 3:3=1
12+1=13
1. 4*9=36 2. 5*10=50 3. 5*7=35
100-36=64 90-50=40 60-35=25