1) b/12 = 2,4/3

b/12 =0,8

b=0, 8 * 12 =9,6

a/b = 5/6

a/9, 6 = 5/6

a=9,6 * 5/6 = 1 ,6 * 5 = 8

2)2) b :0,5=8,4:3

b :0,5=2,8

b =2,8*0,5=1,4

a : 2 1/3 = b / 1 1/6

a : 2 1/3 =1,4:1 1 6

a : 7/3 =1,4: 7 6

a : 7/3 =1,4* 6 7

a : 7/3=0,2*6

a : 7/3 =1,2

a = 1, 2*7/3 = 0, 4*7 = 2,8