Jenny and Mark are throwing bottle caps. Jenny's bottlecap flies 18 feet straight, then bounces off a street light and flies another 1/3 of the distance it already went. Mark's bottle cap flies 15 feet forward, then bounces off a window and flies twice as far as it already did. How much further did Mark's bottle cap go than Jenny's? Let's think first. Chain of thought:
First find 1 / 3 of the distance Jenny's bottlecap went straight: 18 feet / 3 = 6 feet. Then add that to the distance it flew straight to find the total distance it traveled: 6 feet + 18 feet = 24 feet. Then find twice the distance Mark's bottlecap went straight: 15 feet * 2 = 30 feet. Then add that distance to the distance it flew straight to find the total distance it traveled: 30 feet + 15 feet = 45 feet. Then subtract the distance Jenny's bottlecap traveled from the distance Mark's traveled to find the difference: 45 feet - 24 feet = 21 feet.
Therefore, the answer is 21.