Problema Solution
Tina would like to melt down her existing gold jewelry to make a 20 ounce gold necklace that is 90% pure gold. After melting her jewelry, she is left with two batches. One batch is 75% pure. The other batch is 96% pure. How much of the 96% pure melted gold should Tina mix with the 75% pure melted gold to obtain 20 ounces of 90% pure gold?
Answer provided by our tutors
let
x = oz of 75% pure gold
y = oz of 96% pure gold
x + y = 20
0.75*x + 0.96*y = 20*0.90
by solving the system of equations we find
x = 5.71 oz
y = 14.29 pz
click here to see the step by step solution of the system of equations