There are (300/3) x 2 = 100 x 2 = <<300/3*2=200>>200 females cows in the field.
There are 200/2 = <<200/2=100>>100 male cows in the field.
200/2 = <<200/2=100>>100 female cows are spotted.
100/2 = <<100/2=50>>50 male cows have horns.
There are 100 - 50 = <<100-50=50>>50 more females with spots than males with horns.
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