Problema Solution
A jogger ran
2
miles, decreased her speed by 1 mile per hour, and then ran another
3
miles. If her total jogging time was
1415
hours, find her speed for each part of her run.
Answer provided by our tutors
let
v = the speed of the first part of the run, v>0
d1 = 2 mi
v - 1 = the speed of the second part of the run, v - 1 >0, v > 1
d2 = 3 mi
t = 1415 hr the total jogging time
since speed = distance/time we have time = distance/speed
the time of the first part + the time of the second par = the total part
d1/v + d2/(v - 1) = t
2/v + 3/(v - 1) = 1415
by solving we find:
v = 1.00212313 mph
click here to see the step by step solution of the equation:
v - 1 = 1.00212313 - 1 = 0.00212313 mph
the speed of the first part of the run is 1.00212313 mph.
the speed of the second part of the run is 0.00212313 mph.