percent & proportions

Question

a 60 gram ring is made of 14 carat gold. fourteen carat gold is made of gold mixed with copper and has about 40% more gold than copper. is there more than 40 grams of pure gold in the ring

Answer 1

Darlene, if c is the percent of copper, then c + c + 40 = 100

2c = 60

c = 30

 

Then, gold is 70%

 

.7(60) = 42, so yes.

 

Hope this helps!