Due to reduction of 25% in price of oranges a customer can purchase 4 oranges more for Rs. 16. what is original price of an orange?

Recall it is based on inverse proportion or product constancy concept.

     Reducion in price                      increase in amount

         25%     1/4                              1/3   33.33% = 4 oranges

It means original number of oranges = 4 x 3 = 12

original price of oranges = 16/12 = Rs. 1.33