Question 975101
Tanya starts for school walking an average rate of 120 feet per minute.
 She realizes she forgot her lunch turns around and jogs back to house at 360 feet per minute.
 It took 10 minutes to go and come home.
 How far did she walk before she turned around?
:
let d = distance walked before she turned around, (also the distance returned)
:
Write a time equation; time = dist/speed
:
time there + time back = 10 min
{{{d/120}}} + {{{d/360}}} = 10
multiply equation by 360, cancel denominators and you have
3d + d = 360(10)
4d = 3600
d =3600/4
d = 900 ft when she turned around
:
:
Check this; find the time each way.
900/120 = 7.5 min
900/360 = 2.5 min
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total time: 10 min