Ratio Tough Question

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Ratio Tough Question

by engg.manik » Mon Sep 21, 2009 6:03 am
Question -> Two alloy of Copper & Zinc, in the first alloy the ratio of Copper & Zinc is 3:4, in the second alloy the ratio of Copper & Zinc is 6:1, In what proportion should these two alloys be mixed so that a new alloy containing equal part of Copper & Zinc must be added.

Ans :- > 5:1

Can anyone please help with solution

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by a_forest » Mon Sep 21, 2009 6:15 am
Say you need to use x amount of Alloy 1 and y amount of Alloy 2 to balance the Copper and Zinc.

So Copper from Alloy 1 is 3x/7 and from Alloy 2 6y/7.
Zinc from Alloy 1 is 4x/7 and from Alloy 2 y/7.

It follows that 3x+6y=4x+y or x=5y or so the ration is 5:1 (x:y).