Question 360056
You run at 6 mph.  Your Dad leaves 15 min after you and runs at 9 mph.  How long before he catches you?  How far have each of you run?
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you 6mph
dad 9mph
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in 1/4 hour you run 1/4 *6 =3/2 miles
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since both are running in same direction 
the effective speed = 9-6 = 3mph.
time = d/r
t=3/2 / 3
t=3/2 *1/3
t= 1/2 hour
dad catches up after 1/2 hour
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in 1/2 hour you have run 1/2 * 6 = 3 miles
dad has run 1/2 * 9 = 4.5 miles
m.ananth@hotmail.ca
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