Business Mathematics Brief 12th Edition by Stanley Salzman ,Gary Clendenen, Charles Miller

Exercise 153

GOLD Pure gold is 24 karat gold. Due both to the high cost of pure gold and the fact that pure gold is soft and can be bent, gold jewelry is often mixed with an alloy and sold as 18-karat, 14-karat, or 10-karat. Write this fraction in lowest terms.
18 karat = (18 parts gold, 6 parts alloy) _____________