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**Please help. I have been stuck for hours**

In a large marathon, runners start the race in stages. Sophia started in group E and ran at a rate of 4.8 miles per hour. During the race she was passed by Josefina who ran at a rate of 5.3 miles per hour and started in group H, 25 minutes after Sophia started. How far did Sophia run before she was passed by Josefina?
If the answer is not an integer, enter it as an exact decimal.

User Zemil
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1 Answer

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Answer: Sophia ran 21.2 miles before she was passed by Josefina.

Explanation:

Let t represent the time for which Sophia ran before she was passed by Josefina.

Sophia started in group E and ran at a rate of 4.8 miles per hour.

Distance = speed × time

Distance covered by Sophia in t hours would be

4.8 × t = 4.8t

During the race, she was passed by Josefina who ran at a rate of 5.3 miles per hour and started in group H, 25 minutes(25/60 = 5/12 hours) after Sophia started. This mean that time spent by Josefina before she passed Sofia is (t - 5/12) hours.

Distance covered by Josefina would be

5.3(t - 5/12) = 5.3t - 26.5/12

Since they covered the same distance, then

4.8t = 5.3t - 26.5/12

5.3t - 4.8t = 26.5/12

0.5t = 26.5/12

t = 2.208/0.5 = 4.417 hours

Distance run by Sophia before she was passed by Josefina is

4.8t = 4.8 × 4.417 = 21.2 miles