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A person takes a trip, driving with a constant speed of 89.5km/h, except for a 22min rest stop. If the person's average speed is 77,8km/h (a.) how much time is spent on the trip and (b.) how far does the person travel?

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User Adam Puza
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Call x the distance traveled V = x / t = 89.5 = x / t => x = 89.5t Rest time in hours = 22min * 1 h / 60 min = 11/30 h Total time spent on the trip = t + 11/30 => Average speed = 77.8 = x / (t + 11/30)=> x = 77.8 (t + 11/30) => 89.5t = 77.8 (t + 11/30) => 89.5t = 77.8t + 77.8 * 11/30 => 89.5 – 77.8t = 28.527 => 11.7 t = 28.527 => t = 28.527 / 11.7 => t = 2.44 h => t + 11/30 = 2.81 h => x = 89.5t = 89.5 * 2.44 = 218.3 km Answers: a) 2.81 h; b) 218.3 h
User Mustansir Zia
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