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Question 726851: Hi there, i need help solving the question below:
Dolores told Dudley to take a hike, so he did. He hiked for a total of 8 hours with an average speed of 5.5 km/h. Some of the time he walked at a rate of 4 km/h, while the rest of the time he jogged at 10km/h. For how many hours did he walk? How far did he jog?
Thanks
Answer by josgarithmetic(39617)   (Show Source):
You can put this solution on YOUR website! ______________speed____________time___________________distance
walked________4_________________(___)________________(____)
jogged________10_______________(___)________________(____)
What can be done about expressions for time and distance? The total hike time was 8 hours, so try making a sum for this. Let w = walk time and j = job time. Both as hours. w+j=8, so try w=8-j.
______________speed____________time___________________distance
walked________4_______________(8-j)__________________(____)
jogged________10_______________(j)___________________(____)
Next, fill in distances using speed*time=distance.
______________speed____________time___________________distance
walked________4_________________(8-j)________________(4(8-j))
jogged________10________________(j)__________________(10j)
Total_________________________________________________(48)
Note that average speed was 5.5 km/hr, and was for 8 hours. USE this to find the actual distance, speed*time=distance, 5.5*8=44, so this is the total distance.
The information developed in the table gives us now an equation using that one variable which the question asks for, j, although this could have been well enough done for w instead without any complications.
 . Solve for j.
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