A fold density is 19 times greater than the water and for copper it is 9 times. At what ratio you can mix gold
and copper to get 15 times denser than water. ? Answers
A) 3 : 1  B) 3 : 2  C) 3 : 5  D) 3 : 8  E) 3 : 7
Suppose x units of gold are mixed with y units of copper to make (x+y) units of alloy which is 15 times denser than water.   Then 19*x + 9*y = 15*(x + y)   =&gt; 19*x - 15*x = 15*y - 9*y   =&gt; 4*x = 6*y =&gt; x/y = 3/2   So gold and copper should be mixed respectively in the ratio of 3 : 2   ANSWER:3 : 2
<result>B</result>
A fold density is 19 times greater than the water and for copper it is 9 times. At what ratio you can mix gold
and copper to get 15 times denser than water. ?