SOLUTION: you leave your house for school at 7:46 AM traveling at 30mph. Your mom realizes you forgot your lunch and leaves at 7:51 AM traveling at 78 mph. At what time will your mom catch u

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Question 257106: you leave your house for school at 7:46 AM traveling at 30mph. Your mom realizes you forgot your lunch and leaves at 7:51 AM traveling at 78 mph. At what time will your mom catch up to you? The answer is 7:54am but i dont know how to figure it our
Found 2 solutions by rajagopalan, Alan3354:
Answer by rajagopalan(174) (Show Source):
You can put this solution on YOUR website!
Your speed=30 mph
Mom'sspeed=78 mph
Approach velocity=78-30=48 mph
***
At 7:51 distance between mom & you=30*(7:51-7:46)/60
=30*5/60=2.5 miles
mom appraches 48 miles in one hr = 60 minutes
so to cover 1 mile mom will take 60/48=1.25 minutes
to cover 2.5 miles mom will take = 1.25*2.5=3.125 minutes
so mom will meet you at 7:51+3.125=7:54 and 1/8 of a minute

Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website!
In 5 minutes at 30 mph, you've gone 2.5 miles.
Your mom is gaining on you at 48 mph (78-30).
2.5 mi/48 mph = 2.5/48 hours = 3.125 minutes.
751 + 3.125 =~ 7:54