<PRE><B>Question 262893</B>
 Elisa walked a certain distance at 5 mph and then jogged twice that distance at 8 mph. 
Her total time walking and jogging was 2 hours and 15 minutes.
 How far did Elisa get?
:
let d = her walking distance
then
2d = her jogging dist
and
3d = total distance
:
Change 2 hr 15 min to 2.25 hrs
:
Write a time equation: Time = dist/speed
:
Walk time + jog time = total time
{{{d/5}}} + {{{(2d)/8}}} = 2.25
Multiply by 40, results:
8d + 5(2d) = 40(2.25)
8d + 10d = 90
18d = 90
d = {{{90/18}}}
d = 5 mi, walking
then
3(5) = 15 mi total dist
;
:
Check, find the time
5/5 + 10/8 = 
1 + 1.25 = 2.25
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