The ratios of copper and gold in the first and second alloys are 3 : 4 and 2 : 5 respectively. 14 kg of the first alloy are mixed with 21 kg of the second alloy. Find the ratio of copper and gold, respectively, in the new mixture.
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Correct answer: D
Explanation
The correct answer is option 4 i.e. 12 : 23.
Given:
The ratio of copper and gold in the first alloy = 3 : 4
The ratio of copper and gold in the second alloy = 2 : 5.
Explanation:
Alloy = Copper : Gold
First = (3 : 4) × 2 = 6 : 8
Second = (2 : 5) × 3 = 6 : 15
So, the final ratio of the mixture
Copper : Gold
⇒ (6 + 6) : (8 + 15)
⇒ 12 : 23