SSC CGL (Prelims) Maths: Ratio and Proportion questions with solutions

Q1. A money bag contains one-rupee, five-rupee, and ten-rupee coins in the ratio 3:5:7 respectively. If the total amount in the bag is ₹980, then find the number of ₹10 coins.

1. 69
2. 70
3. 71
4. 68

Answer: 70

If the numbers of coins are \(3x, 5x, 7x\), then total value is \(1\cdot 3x + 5\cdot 5x + 10\cdot 7x = 3x+25x+70x=98x\). Since the total amount is ₹980, \(98x=980\), so \(x=10\). Thus the number of ₹10 coins is \(7x=70\).