210 boxesStep-by-step explanation:1. A machine can produce 120 boxes in 4 hours. How many boxes will it produce in 7 hours if it works at the same rate? Kind of Proportion: Direct Proportion Solution This is a direct proportion because the number of boxes produced is directly proportional to the number of hours the machine works. As the number of hours increases, the number of boxes produced also increases. We can set up a proportion 120 boxes / 4 hours = x boxes / 7 hours To solve for x, we cross-multiply: 4 * x = 120 * 7 4x = 840 x = 840 / 4 x = 210