SOLUTION: How many ounces of pure zinc must be added to 20 ounces of brass which is 30% zinc and 70% copper to produce brass that is 40% zinc?

Question 405972: How many ounces of pure zinc must be added to 20 ounces of brass which is 30% zinc and 70% copper to produce brass that is 40% zinc?
Answer by mananth(16946) (Show Source): You can put this solution on YOUR website!
percent ---------------- quantity
30 ---------------- 20 brass
100 ---------------- x Zinc
40 ---------------- 20+x Mixture

30*20+100*x=40(20+x)

600+100 x=800+40x

100x-40x=800-600

60x=200

/60
x=3.33 ounces of pure Zinc

RELATED QUESTIONS
How many ounces of pure zinc must be alloyed with 20 ounces of brass that is 30% zinc and (answered by josgarithmetic)

Brass is made of a mixture of zinc and copper. How many ounces of pure zinc must be mixed (answered by Fombitz)

By weight, an alloy of brass is 60% copper and 40% zinc. Another alloy of brass is 30%... (answered by galactus)

Brass is an alloy created using 80% copper and 20% zinc. If Henri�s brass trumpet... (answered by checkley77)

You have a vast quantity of yellow brass - 67% copper and 33% zinc - and red brass - 85%... (answered by ptaylor)

In general brass is made of two parts of copper to one part zinc. How many pounds of zinc (answered by stanbon)

Brass is an alloy containing only copper and zinc. A particular batch of brass is... (answered by ankor@dixie-net.com)

If the price of copper is 65 cents/lb and the price of zinc is 30 cents/lb, how many... (answered by ankor@dixie-net.com)

a lot of brass scrap weighing 350 kg contains 30% zinc. how many kg of zinc must be added (answered by ankor@dixie-net.com)