# math

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A woman drove to work at an average speed of 40 miles per hour and returned along the same route at 30 miles per hour. If her total traveling time was 1 hour, what was the total number of miles in the round trip?

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Her average speed was 35 miles per hour. Since the round trip took her 1 hour, what was the total number of miles in the round trip?

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went t hours at 40
went (1-t) at 30
so
40 t = 30 (1-t)
70 t = 30
t = 3/7 of an hour
distance at 40 = (3/7)(40) = 120/7
distance at 30 = (4/7)(30) = 120/7 better be the same:) check
so total distance = 240/7

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I forgot to mention that this is an SAT question of the Day and they give you options for answers. The options are:
30
30 1/7
34 2/7
35
40
Sorry if the way I put it was confusing.

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240/7 = 34 2/7
not allowed to use average because distance, not time, is the same

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I did not see that SAT question of the day. I usually do them.

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Oh, this question is from a while ago. They are very helpful in preparing for the SAT. Thank you for your help.