SOLUTION: Beavis and Butthead steal their neighbor's riding lawnmower and drive away at a constant speed of 15 miles per hour. Five minutes later, their neighbor jumps onto Butthead's skat

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Question 82372: Beavis and Butthead steal their neighbor's riding lawnmower and drive away at a constant speed of 15 miles per hour. Five minutes later, their neighbor jumps onto Butthead's skateboard and chases after them at a constant speed of 20 miles per hour. Find the neighbor's travel time needed to catch Beavis and Butthead. Give your final answer in hours.
Answer by askmemath(368) About Me  (Show Source):
You can put this solution on YOUR website!
Since everything is is minutes, we'll first find the answer in minutes and then convert it to hours
In 1min Beavis and Butthead would have covered 15/60 miles = 1/4miles
In 5mins Beavis and Butthead would have covered 15/60 miles =5x( 1/4miles) = 5/4 = 1.25miles
Now the neighbour starts chasing them at 20miles per hour
Effective speed = 20-15 = 5miles per hour = 5/60 = 1/12mile per minute
Time taken to cover 5/4 miles = (5/4) / (1/12) = 15mins
Time taken in hours = 15/60 = 1/4 = .25hours