A painter took a digital photo of a 16-inch wide by 20-inch long painting to display on his website. The digital image is 2.5 inches long. What is the area of the image in square inches?
The actual photo has an area of 16*20 inches, so 320 inches squared. The ratio between the digital and real photo is 16:20. On the other hand, the width to length of the digital photo is x:2.5. Cross multiply the two ratios and solve for x. 16/20*x/2.5 —> 20x = 40 —> x = 2. The width of the digital image is 2 inches, so multiplying the width times the length gives you a 5 inches squared area for the digital image. Answer: 5 in^2
