Civil Service Exam Reviewer · Ratio and Proportion · hard
Alloy X contains gold and copper in the ratio 1 : 2; alloy Y contains them in the ratio 1 : 3. If equal weights of X and Y are melted together, what is the ratio of gold to copper in the new alloy?
- 7 : 17
- 2 : 5
- 17 : 7
- 1 : 6
Answer
A. 7 : 17
Solution
Take 12 units of each. Gold = 4 + 3 = 7; copper = 8 + 9 = 17. Ratio = 7 : 17.
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