Question 1101214
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The ratio of the two speeds is 468:390 = 6:5.<br>
Since the distances are the same, the ratio of times is 5:6.<br>
Since the total time was 11 hours, 5 hours were at the higher speed and 6 hours were at the lower speed.<br>
The question asks for the time for the return trip (at the lower speed); the answer is 6 hours.<br>
Answer B.