Use proportions to solve this. Set up the ratios with dollars on the top and pounds on the bottom and then cross-multiply to solve for x. Like this: [tex] \frac{d}{p}: \frac{800}{560}= \frac{300}{x} [/tex]. Cross multiplying gives us 800x=168,000. Divide by 800 to get that x = 210. So $300 equals 210 pounds.
