Q. A and B are two alloys of gold and copper prepared by mixing metals in the ratio 7: 2 and 7: 11 respectively. If equal quantities of the alloys are melted to form a third alloy C, the ratio of gold and copper in C will be? 

1. 5 : 9
2. 5 : 7
3. 7 : 5
4. 9 : 5