Question 277442
How many pounds of a certain alloy containing 35% silver must be melted with another alloy containing 65% silver to obtain 50 pounds of an alloy containing 50% silver?

let us mix x pounds of 35% alloy

So the 65% alloy mixed will be 50-x pounds


when added the mix is 50 pound and 50% 

0.35x+0.65(50-x)=0.5*50

0.35x+32.5 - 0.65x = 25

-0.3x=-32.5+25

-0.3x= -7.5

x=7.5/0.3   = 25  pounds of 35% silver alloy