取两份乙分别冶炼合金可如下列式计算——
甲样品的含金量：
[(1+3.5)×2×47/75-(1+2)×68%]÷(3.5×2-1)
=[9×47/75-3×17/25]÷6
=[3×47/25-3×17/25]÷6
=[3×30/25]÷6
=15/25
=60%
乙样品的含金量：
[(1+2)×68%-1×60%]÷2
=[3×0.68-0.6]÷2
=[3×0.68-0.6]÷2
=1.44÷2
=0.72
=72%
以上是算术解答.
注：这种问题更适合用方程解答,设甲样品的含金量为x,乙样品的含金量y,则
(x+2y)/(1+2)=0.68
(3.5x+y)/(1+3.5)=47/75
可解得
x=60%
y=72%