Question
The price of 3 mobiles and 6 pen drives is Rs. 9,000 and
the price of 2 mobiles and 8 pen drives is also Rs. 9,000. What is the difference between the price of one pen drive and one mobile?Solution
As per the question, instead of 1 mobile(M), one can purchase 2 pen drives(PD). ∴ Price of 1 M = price of 2 PD Given, price of 3 M + 6 PD = 9,000 ∴ Price of 3 M + 3 M = 9,000 (As 6 PD = 3 M) ∴ 6 M = 9,000 ∴ 1 M = Rs.1, 500 and Price of 1 PD = Rs. 750 ∴ Reqd. difference = Rs.1, 500 - Rs. 750 = Rs. 750
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