甲体积V1=M/P1
乙体积V2=M/P2
总体积V=V1+V2
总质量2*M
合金密度P=2*M/V=2*M/(V1+V2)=2*M/(M/P1+M/P2)=2/(1/P1+1/P2)=2/(P2/(P1*P2)+P1/(P1*P2))=2*P1*P2/(P1+P2)
甲体积V1=M/P1
乙体积V2=M/P2
总体积V=V1+V2
总质量2*M
合金密度P=2*M/V=2*M/(V1+V2)=2*M/(M/P1+M/P2)=2/(1/P1+1/P2)=2/(P2/(P1*P2)+P1/(P1*P2))=2*P1*P2/(P1+P2)