OG详解-OG9 数学1 Q3

Choice B is correct. It’s given that Ty plans to walk at an average speed of 4 kilometers per hour. The number of kilometers Ty will walk is determined by the expression 4s, where s is the number of hours Ty walks. The given goal of at least 24 kilometers means that the inequality s4≥24 represents the situation. Dividing both sides of this inequality by 4 gives s≥6, which corresponds to a minimum of 6 hours Ty must walk.
Choice A is incorrect and may result from conceptual or calculation errors. 
Choice C is incorrect and may result from conceptual or calculation errors. 
Choice D is incorrect and may result from conceptual or calculation errors.