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A reduction of 10℅ in the price of tea enables a dealer to purchase 25 kg more tea for Rs22500. what is the reduced price per kg of tea? Also find the original price per kg.

In an examination, 70℅ students passed in maths and 75℅ in science while 20℅ failed in both the subjects. If 260 students passed in both the subjects, the total number of students is ?