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If Ritu were younger by 5 years than what she really is, then the square of her age would have been 11 more than five times her present age. What is her present age?

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Question 6 (Choice 1) If Ritu were younger by 5 years than what she really is, then the square of her age would have been 11 more than five times her present age. What is her present age? Let Present age of Ritu = x years Given that If Ritu were younger by 5 years than what she really is, then the square of her age would have been 11 more than five times her present age. (Ritu’s age − 5)2 = 5 × Present Age + 11 (x − 5)2 = 5x + 11 x2 + 52 − 10x = 5x + 11 x2 + 25 − 10x = 5x + 11 x2 − 10x − 5x + 25 − 11 = 0 x2 − 15x + 14 = 0 x2 − 14x − x + 14 = 0 x(x − 14) − 1(x − 14) = 0 (x − 1) (x − 14) = 0 ∴ x = 1, x = 14 But x = 1 is not possible as Ritu’s age 5 years ago cannot be negative Thus, x = 14 ∴ Ritu’s Present Age = 14 years

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Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 12 years. He provides courses for Maths and Science at Teachoo.