SOLUTION: eighteen karat gold contains 18 parts gold and 6 parts other metals. amy's new ring contains 12 parts gold and 3 parts other metals. is the ring 18 karat gold? why?

Question 679169: eighteen karat gold contains 18 parts gold and 6 parts other metals. amy's new ring contains 12 parts gold and 3 parts other metals. is the ring 18 karat gold? why?
Answer by ptaylor(2198) (Show Source): You can put this solution on YOUR website!
18 Karat gold contains 18 parts gold and 6 parts other metals. This means that out of every 18+6=24 parts 18/24 is gold (75%) and 6/24 is other metals(25%).
If Amy's new ring contains 12 parts gold and 3 parts other metals that means that out of every 12+3=15 parts 12/15 is gold (80%) and 3/15 is other metals(20%).
The answer is NO!. Amy's ring is more pure than 18 Karat gold.
Hope this helps---ptaylor
RELATED QUESTIONS
Eighteen-carat gold contains 18 parts by mass of gold to 6 parts of other metals.... (answered by ankor@dixie-net.com)

Eighteen carat gold contains 18 parts by mass of gold to 6 parts of other metals.... (answered by josgarithmetic)

The purity of gold is measured in karats, with pure gold being 24 karats. Other purities... (answered by timofer)

I need help with this!!! Here is the question. The purity of gold is measured in... (answered by vleith,stanbon)

The purity of gold is measured in karats, with pure gold being 24 karats. Other purities... (answered by ankor@dixie-net.com)

Hello Tutors, the problem I am having trouble with is the following: The purity of... (answered by josgarithmetic,greenestamps)

For thousands of years, gold has been considered one of the Earth's most precious metals. (answered by mananth)

Pure, or 24-karat,gold is very soft, so it is rarely used for jewellery. Most gold... (answered by josgarithmetic)

A chemist made a mixture of 3 parts of copper and 5 parts of gold. He wants to change the (answered by math-vortex)