问答题A car traveled from A to B in 30 minutes. The first half of the trip was covered at 50 mph, and the second half at 60 mph. What was the average speed?400/11 - 500/11 - 600/11 - 700/11

问答题
A car traveled from A to B in 30 minutes. The first half of the trip was covered at 50 mph, and the second half at 60 mph. What was the average speed?400/11 - 500/11 - 600/11 - 700/11

参考解析

解析:
这是一道计算题,我们设平均时速为X,则0.25X/50+0.25X/60=0.5,进而可得X=600/11,因此该选600/11。

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