question_answer

There were two different copper alloys of total weight 50 kg. The first contains 40% less copper than the second. Determine the percentage of copper in the first and second alloys, if it is known that there were 6 kg of copper in the first alloy and 12 kg in the second.

A)  20%, 80%                    

B)  16%, 78%

C)  20%, 60%        

D)  30%, 70%

E)  None of these