An alloy is to contain copper and zinc in the ratio 7 : 3. The zinc required (in kg) to be melted with 35 kg of copper, is?
Choose the correct choice
A) 10 and 2/3  B) 15  C) 9 and 2/3  D) 9  E) 10
Explanation :   7 : 3 : 35 : x   =&gt; 7x = 3 * 35   =&gt; x = (3*35)/7= 
<gadget id="calculator">(3*35)/7</gadget>
<output>15</output>
15 Kg.   Hence 15.   Answer : 15
<result>B</result>
An alloy is to contain copper and zinc in the ratio 7 : 3. The zinc required (in kg) to be melted with 35 kg of copper, is?