Mr. Salazar had 7 x 12 = <<7*12=84>>84 oranges.
He reserved 84 x 1/4 = <<84*1/4=21>>21 oranges for his friend.
Ha had 84 - 21 = <<84-21=63>>63 oranges to be sold yesterday.
But only 63 x 3/7 = <<63*3/7=27>>27 oranges were sold yesterday.
So, he had 63 - 27 = <<63-27=36>>36 oranges left.
Since four oranges are rotten, then only 36 - 4 = <<36-4=32>>32 oranges are left to be sold today.
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