<PRE><B>Question 1143482</B>
James can jog twice as fast as he can walk.
 He was able to jog the first 9 miles to his grandmother’s house, but then he tired and walked the remaining 1.5 miles.
 If the total trip took 2 hours, then what was his average jogging speed?
:
let j = his jogging speed
he walks half as fast, therefore
.5j = his walking speed 
:
write a time equation, time = dist/speed
jog time + walk time = 2 hrs
{{{9/j}}} + {{{1.5/(.5j)}}} = 2
multiply by .5j
.5(9) + (1.5) = .5j(2)
4.5 + .1.5 = j
6 = j
j = 6 mph is the jogging speed
:
:
Check, find the actual time of each
9/6 = 1.5 hrs
1.5/3 = .5 hrs
-----------------
total time 2 hrs
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