A man traveled to his country home, a distance of 150 miles and then back. His average rate of speed going was 50 miles an hour and his average return speed was 30 miles per hour. His average rate of speed for the entire trip was Need help will mark brainlist

  37.5 mi/h

Step-by-step explanation:

  time = distance / speed

On the trip 'going', the time was (150 mi)/(50 mi/h) = 3 h.

On the return trip, the time was (150 mi)/(30 mi/h) = 5 h.

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  speed = distance / time

The average speed for the whole trip was ...

  speed = (150 mi +150 mi)/(3 h +5 h) = (300 mi)/(8 h) = 37.5 mi/h

His average rate of speed was 37.5 miles per hour.

its the fourth option

answer: the common difference is -0.10