Question
Ravi visits an electronics store with a certain amount
of money. He can buy 50 USB drives or 25 headphones with the money he has. However, he decides to save 20% of the amount for a concert ticket and buys 10 headphones and some USB drives. Calculate the percentage of USB drives he can now purchase out of the initial number of USB drives he could have bought.Solution
ATQ Let the amount of money with Ravi be Rs. '100a' So, the price of 1 USB drive = (100/50) = Rs. '2a' Also, the price of 1 headphone = (100/25) = Rs. '4a' ATQ; Amount retained for the concert ticket = 0.20 X 100a = Rs. '20a' Price of 10 headphones = 10 X 4a = Rs. '40a' Remaining amount = 100a - 20a - 40a = Rs. '40a' So, number of USB drives he can purchase now = (40a/2a) = 20 Therefore, required percent = (20/50) X 100 = 40%
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