Answer:
1st box = 2/3
2nd box = 16/3
==============================================
Work Shown for the 1st box
2/3 = x/1
x = 2/3
There's not much in terms of steps
------------
Another approach for the 1st box
2/x = 3/1
2*1 = x*3
2 = 3x
x = 2/3
------------
Work Shown for the 2nd box
2/3 = x/8
2*8 = 3*x ... cross multiplying
16 = 3x
x = 16/3
Optionally this can be converted into a mixed number
16/3 = (15+1)/3
16/3 = 15/3 + 1/3
16/3 = 5 + 1/3
16/3 = 5 & 1/3