SOLUTION: Enrique runs an average speed of 6 mph. Half an hour later, Enrique's brother leaves the house running at an average speed of 8 mph. How long will it tak Enrique's brother to run h

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Question 222985: Enrique runs an average speed of 6 mph. Half an hour later, Enrique's brother leaves the house running at an average speed of 8 mph. How long will it tak Enrique's brother to run half the distance that Enrique has run?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Enrique runs an average speed of 6 mph.
Half an hour later, Enrique's brother leaves the house running at an average speed of 8 mph.
How long will it take Enrique's brother to run half the distance that Enrique has run?
:
Let t = running time of E's bro to run half the distance
then
(t+.5) = E's time to run the whole distance
:
Write a distance equation: Dist = speed * time
:
E's dist = twice E's bro dist
6(t+.5) = 2(8t)
:
6t + 3 = 16t
:
3 = 16t - 6t
:
3 = 10t
t = 3%2F10
t = 3/10 hrs (18 min) for E's bro to run half the distance
;
;
Check solution by finding the running dist of each
8*.3 = 2.4 mi
:
6*(.3+.5) = 4.8 mi