SOLUTION: Russ and Janet are running in the Apple Hill Fun Run. Russ runs at 7 mph, Janet runs at 5 mph. If they start at the same time, how long will it be before they are half a mile apart

Question 177645: Russ and Janet are running in the Apple Hill Fun Run. Russ runs at 7 mph, Janet runs at 5 mph. If they start at the same time, how long will it be before they are half a mile apart? show me step by step..
Answer by solver91311(24713) (Show Source): You can put this solution on YOUR website!
The trick here is to recognize that you are dealing with a relative motion problem. The answer would be the same if one of them was going 98 miles per hour and the other one 100 mph -- or more to the point, if Janet stood still and Ryan went 2 mph. So, how long would it take Ryan to go half a mile at 2 mph?
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