To solve this, they are giving you an equal amount of 8 boxes, but we are going to use 4 in this case, let's leave the other 4 for later.
So the fraction is 3/4 which means out of four things (we are using boxes in this case) three of them are going to be shaded.
So, in the top row, you shade three boxes, and you do the same with the bottom.
Another fraction for 3/4 would be 6/8 because since you shaded 3 out of the 4 from the top, and 3 out of the 4 from the bottom, it will give you an equal of 6 boxes that are shaded out of a total of 8 boxes.
I hope this helps.
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