GATE CS 2024 Set 1 — Question 4

Let the number of coins of ₹1, ₹5, and ₹10 be $5x$, $3x$, and $13x$ respectively.The total value of the coins is calculated as follows:

• Value of ₹1 coins = $5x \times 1 = 5x$
• Value of ₹5 coins = $3x \times 5 = 15x$
• Value of ₹10 coins = $13x \times 10 = 130x$

Total amount = $5x + 15x + 130x = 150x$The percentage of money in ₹5 coins is:$$\frac{\text{Value of ₹5 coins}}{\text{Total amount}} \times 100 = \frac{15x}{150x} \times 100$$$$= \frac{1}{10} \times 100 = 10\%$$Thus, the correct option is (C).