Question 14 - MCQs from NCERT Exemplar - Chapter 3 Class 10 Pair of Linear Equations in Two Variables

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Question 14 Aruna has only ₹ 1 and ₹ 2 coins with her. If the total number of coins that she has is 50 and the amount of money with her is ` 75, then the number of ₹ 1 and ₹ 2 coins are, respectively 35 and 15 (b) 35 and 20 (c) 15 and 35 (d) 25 and 25 Let Number of ₹ 1 coins = x Number of ₹ 2 coins = y Given that Total coins = 50 x + y = 50 Also, Total money she has = 75 1 × x + 2 × y = 75 x + 2y = 75 So, our equations are x + y = 50 …(1) x + 2y = 75 …(2) Subtracting (2) and (1) (x + 2y) − (x + y) = 75 − 50 y = 25 Putting y = 25 in (1) x + y = 50 x + 25 = 50 x = 50 − 25 x = 25 Thus, x = 25, y = 25 So, the correct answer is (D) x + y = 50 x + 25 = 50 x = 50 − 25 x = 25 Thus, x = 25, y = 25 So, the correct answer is (D) x + y = 50 x + 25 = 50 x = 50 − 25 x = 25 Thus, x = 25, y = 25 So, the correct answer is (D)