Question

An alloy of 9 CT gold contains gold,copper zinc, and silver in the ratio 9:12,5:2,5.
1. Express this ratio in it's simplest form.
2.how much silver would you need if your alloy contained 6g of pure gold?
3.how much copper zinc would you need to make a 9 ct alloy using three grams of pure gold.

Answer 1

Ratio : 9:12.5:2.5

So, gold silver and are in ratio 9:2.5

Hence silver in the alloy which contains 6 gram of Gold = $\frac{2.5}{9}\times6=1.67 \,grams$

As gold and copper & zinc are in ratio 9:12.5

copper & zinc for 3 grams of gold =$\frac{12.5}{9}\times3=4.17\, grams$