In an alloy of zinc, copper and tin in the ratio of 2 : 3 : 1 and other contains copper, tin and lead in the ratio of 5  : 4 : 3.  If equal weights of both the alloys are melted together to form a third alloy, then the weight of lead per kg in the new alloy is?

0.125 Kg

In 1st alloy:

    Zinc  :  Cop.  :   Tin                                

       2   :    3     :  1      = 6                           

In 2nd alloy:

  Cop.  :   Tin   :  Lead

    5    :     4    :    3    =  12

(Make total of 1st and 2nd equal, multiple by 2 in 1st alloy ratio)

In 1st alloy:

    Zinc  :  Cop.  :   Tin                                

      4    :    6     :    2   = 12                           

In 2nd alloy:

  Cop.  :   Tin   :  Lead

    5    :     4    :    3    =  12

⇒

Zinc  :  Cop.  :   Tin   :   Lead

  4    :    6     :     2

             5     :     4   :     3 

  4    :    11    :    6    :     3       = 24 (Total After mixing)

Weight of Lead in the mixture = \(\frac{3}{24}\) = \(\frac{1}{8}\) = 0.125 Kg.