The double number line shows the approximate number of ounces in a certain number of pounds: two number lines are shown. the one on top is labeled pounds and has tick marks labeled 1, 2, and 3 with secondary tick marks in between. the one on bottom is labeled ounces and has tick marks labeled 8, 24, and 40 with secondary tick marks in between. the first tick mark on pounds lines up vertically with the first secondary tick mark on the ounces line, and the remaining tick marks all line up. based on the number line, about how many ounces are there in 5 pounds? 21 ounces 40 ounces 64 ounces 80 ounces