Mr. Salazar had seven dozen oranges. He reserved 1/4 of it for his friend and was able to sell 3/7 of the remaining yesterday. Today, he saw four rotten oranges. How many oranges are left to be sold today? Let's think first. Chain of thought:
Mr. Salazar had 7 x 12 = 84 oranges. He reserved 84 x 1 / 4 = 21 oranges for his friend. Ha had 84 - 21 = 63 oranges to be sold yesterday. But only 63 x 3 / 7 = 27 oranges were sold yesterday. So, he had 63 - 27 = 36 oranges left. Since four oranges are rotten, then only 36 - 4 = 32 oranges are left to be sold today.
Therefore, the answer is 32.