0.47% = 0.0047 in decimal form. Percent means 'per 57'. So, 67Inches means 0.47 per 100 or simply 0.47/100. If you divide 0.47 by 100, you'll get 0.0047 (a decimal number).
Yvette wants to earn a profit of $360, then. That means she has to make a total of $480. 480 divided by 18 is 26 and 2/3. That basically rounds up to $26.67.
480 = 18x
360 = 18x - 120
120(3) = 18x - 120
(I'm not that good at this, so don't take my word for it)