A. B is 496 kilometers away. Car a goes from a to B at 32 kilometers an hour. Half an hour after car a leaves, car B goes from B to a at twice the speed of car A. how many hours after car B leaves, do the two cars meet? The number of watermelons from the fruit shop is twice that of the brandy melons. If you buy 40 brandy melons and 50 watermelons every day, there will be 360 watermelons left when the brandy melons are sold out in a few days. How many watermelons and brandy melons are delivered from the fruit shop?
1. Let two cars meet after X hours. There are: 32 * 0.5 + (32 + 64) x = 496, that is: x = (496-32 * 0.5) / (32 + 64) x = 480 / 96 get: x = 5 answer: B meets a 5 hours later. 2. Analysis: the first condition tells: "the number of watermelons transported by the fruit shop is twice that of the brandy melons", we can find an equivalent relationship
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