An alloy contains only zinc and copper. One such alloy weighing 15-gm contains zinc and copper in the ratio of 2: 3 by weight. If 10 gm of zinc is added then find what amount of copper has to be removed from the alloy such that the final alloy has zinc and copper in the ratio of 4:1 by weight?  Choose the correct choice from the following answers:
A) 5 gm
B) 5.5 gm
C) 6 gm
D) 4.8 gm
E) 5.8 gm
Weight of zinc in the alloy= 6 gm and weight of copper in the alloy = 9 gms.   Suppose ’x’ gms of copper is removed.   Weight of copper in the alloy=9 - x   Weight of zinc in the alloy=6 + 10= 
<gadget id="calculator">6 + 10</gadget>
<output>16</output>
16.   Now,16= 4(9 - x)   Therefore x = 5 gm   5 gmNSWER:5 gm
<result>A</result>
An alloy contains only zinc and copper. One such alloy weighing 15-gm contains zinc and copper in the ratio of 2: 3 by weight. If 10 gm of zinc is added then find what amount of copper has to be removed from the alloy such that the final alloy has zinc and copper in the ratio of 4:1 by weight?