5 : 10 = x : 8 ,
10*x = 8 * 5
10x = 40
x = 40 : 10
x = 4
6 : 2 = 80 : x
6*x = 80 * 2
6x = 160
x = 160 : 6
x = 26 2/3
5 : 10 = x : 8 ,
10*x = 8 * 5
10x = 40
x = 40 : 10
x = 4
6 : 2 = 80 : x
6*x = 80 * 2
6x = 160
x = 160 : 6
x = 26 2/3