A bag contains 25p, 10p and 5p coins in the ratio 2:3:4, amounting to Rs. 242. Find the number of 10p coins.
726
660
760
400
Explanation:
Let the number of 25p, 10p and 5p coins be 2X, 3X and 4X respectively.
We know that, four 25p coins make 1 rupee and ten 10p coins make 1 rupee and twenty 5 paise coins make 1 rupee.
Threfore,
Amount in rupees corresponding to 2X number of 25p coins = 2X/4=X/2
Amount in rupees corresponding to 3X number of 10p coins = 3X/10
Amount in rupees corresponding to 4X number of 5p coins = 4X/20=X/5
But you know that the total amount is Rs. 242. So you can write,
X/2 + 3X/10 + X/5 = 242
(5x + 3x + 2x) / 10 = 242
10x /10= 242
X = 242
Number of 10p coins = 3 x X = 3 x 242 = 726
Let the number of 25p, 10p and 5p coins be 2X, 3X and 4X respectively.
We know that, four 25p coins make 1 rupee and ten 10p coins make 1 rupee and twenty 5 paise coins make 1 rupee.
Threfore,
Amount in rupees corresponding to 2X number of 25p coins = 2X/4=X/2
Amount in rupees corresponding to 3X number of 10p coins = 3X/10
Amount in rupees corresponding to 4X number of 5p coins = 4X/20=X/5
But you know that the total amount is Rs. 242. So you can write,
X/2 + 3X/10 + X/5 = 242
(5x + 3x + 2x) / 10 = 242
10x /10= 242
X = 242
Number of 10p coins = 3 x X = 3 x 242 = 726