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notamathlete
Jan 29, 2009, 05:51 AM
On a treadmill, Daisy walks a distance of 2km. She then doubles the speed of the treadmill and jogs for another 2km. If the total time spent on the treadmill was 1 hour, find the speeds at which she walks and jogs.

Help?

Stratmando
Jan 29, 2009, 06:01 AM
Without math, I would say 40 minutes walking, 20 minutes jogging.

Capuchin
Jan 29, 2009, 06:50 AM
Without math, I would say 40 minutes walking, 20 minutes jogging.

This is correct, just work out the speed from here, have a go! :)

HuiLi
Feb 12, 2010, 07:11 PM
Let x be the speed Daisy walks.
When Daisy doubles the speed(jogs),the speed becomes 2x
Time taken is 1h,so 3x=1h
3x is the total speed of the treadmill.
so 1h=60 minutes
x=60/3
=20minutes walking
speed of Daisy walking:
= distance/time
=2/20
=0.1km/min
to change to hour:
0.1x60mintues(1h)=6km/h

The time Daisy jog at is:
2x=20x2
=40minutes
Speed of Daisy jogging:
=distance/time
=2/40
=0.05km/min
To change it to hour:
0.05x60minutes(1h)
=3km/h

Therefore,Daisy walk at a speed of 6km/h
and she jog at the speed of 3km/h