How much does Gopal need to earn?

 Gopal runs a shop for which he buys 700 Rs worth of supplies every morning. He pays tax of 20 % on the sale value every evening. He takes the balance home. How much should he sell every day if he has to keep Rs 700 for buying supplies next day and get Rs 300 for his personal expenses of the day?

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Srinivasan Ramani 

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