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duffman11
Oct 2, 2008, 01:12 PM
A woman begins jogging at 3pm, running due north at a 6 minute/mile pace. Later she reverses direction and runs due south at a 7 minute/mile pace. If she returns to her starting point at 3:45, find the total number of miles run.

I usually make a chart for Speed, Distance, Time problems such as these.
S D T
A 6min/mile x x/6min/mile t=d/s


B 7min/mile x x/7min/mile

Let x be the distance travelled by the woman.
I figure X is = to both distance A and B since she runs the same distance there and back.
The speeds are given and to find time I divide distance by speed. Here's what I get for an equation:

6x+7x=45

I've tried it several ways so far and I just can't seem to get the right equation. Where am I going wrong!

galactus
Oct 2, 2008, 06:04 PM
This problem is worded wacky. Be careful of units. It is in minutes per mile instead of miles per minute.

d=rt. If it takes 6 minutes to run a mile, that is 10 mph.

If it takes 7 minutes to run a mile on the way back, then that is about 8.57 mph.

45 minutes is 3/4 hours.

6t=d on the way up.

The distances are the same up and back.

So, the distance back is 7(3/4-t)

mygod123456789
Oct 30, 2010, 11:31 AM
ERISON VALDEZ ANSWER

MINUTES=MT START RUNNING AT 3:00PM NORTH
NORTH=N 3:06=1mlN
SOUTH=S 3:12=2mlN
MILES=ml 3:18=3mlN
3:24=4mlN
REVERSE TO BEGIN SOUTH
3:31=1mlS
3:38=2mlS
3:45=3mlS
TOTAL MILES RAN IN 45 MINUTES=
4mlN+3mlS=7ml in 45 minutes

mygod123456789
Oct 30, 2010, 11:34 AM
Nicw neatly understanding