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Rs 9000 were divided equally among a certain number of persons. Had there been 20more persons, each would have got Rs 160 less. Find the original number of persons. |
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Answer» Let the original no. of persons be x, then 9000 divided equally between x persons, each one get ------> 9000/x9000 divided equally between (x + 20) persons, each one get------> 9000/(x + 20)According to the que,9000/(x + 20) = 9000/x - 160=> 9000x = (x+20)(9000 - 160x) => 9000x = 9000x - 160x^2 + 180000 - 3200x=> 160x^2 + 3200x - 180000 = 0=> x^2 + 20x - 1125 = 0=> x^2 + 45x - 25x - 1125 = 0=> x(x + 45) - 25(x + 45) = 0=> (x + 45)(x - 25) = 0 Either (x + 45) = 0 or ( x - 25) = 0 (x + 45) = 0 => x = - 45 (not possible) Therefore, (x - 25) = 0 => x = 25. ans |
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