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 

(a) 35 and 15  

(b) 35 and 20 

(c) 15 and 35  

(d) 25 and 25

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Transcript

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)

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.