Question
A box contains Rs. 930 in coins of Rs. 2, Rs. 5, and Rs.
8 denominations. The ratio of number of coins of Rs. 2, Rs. 5, and Rs. 8 is 6:5:7 respectively. Find the difference between the amount contributed by Rs. 8 coins and Rs. 2 coins.Solution
ATQ,
Let the number of coins of Rs. 2, Rs. 5 and Rs. 8 be 6x, 5x and 7x respectively. ATQ, (6x × 2 + 5x × 5 + 7x × 8) = Rs. 930 (12x + 25x + 56x) = 930 93x = 930 x = 10 Therefore, required difference = (7x × 8 - 6x × 2) = (56x - 12x) = 44x = 44 × 10 = Rs. 440
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