agginuwu
contestada

An alloy of copper and zinc which contains 5 grams of zinc. If 15 grams of zinc are added to this alloy, a new alloy is obtained in which the copper content has been reduced by 30% from the original. Find the initial mass of the alloy

Respuesta :

Answer:

Initial mass = 25 grams

Step-by-step explanation:

[tex]\left(\frac{x}{x+20}\right)\:=\:\:\left(\frac{x}{x+5}\:-.3\:\right)[/tex]

x = 20 (mass of copper)

[tex]\frac{20}{20+5} = .8 = 80[/tex] percent

[tex]\\\frac{20}{20+15} = .5 = 50[/tex] percent  

Otras preguntas