Average Speed to and From a Place: Solved Equation

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The equation 240/s + 240/(s+11) = 8 was solved to yield s = 55 and s = -6, but -6 is not a valid speed for a car. The discussion clarifies that the program likely requires the two speeds for a round trip, specifically s and s+11. It emphasizes the need for proper notation in the equation to avoid confusion. The user is encouraged to interpret 55 as a reasonable speed and to consider adding 11 to find the second speed. The conversation highlights the importance of correctly following homework guidelines and using appropriate tools for posting.
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I've solved my equation, which was originally 240/s + 240/s+ 11 = 8 as, s = 55 and s = -6. It's asking for the average speed to and from a place.It asks me to use s and s+11 and s as my two speeds, but I've tried using 55 and -6 both, it solves all portions of the equation, but I'm lost as what to do next. The program doesn't say what to do next, it just says tell me the answer.
 
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Tyrion101 said:
I've solved my equation, which was originally 240/s + 240/s+ 11 = 8 as, s = 55 and s = -6. It's asking for the average speed to and from a place.It asks me to use s and s+11 and s as my two speeds, but I've tried using 55 and -6 both, it solves all portions of the equation, but I'm lost as what to do next. The program doesn't say what to do next, it just says tell me the answer.
Is the program asking for the two speeds for the round trip? If so, 55 and -6 are NOT the answers. -6 is not a reasonable answer unless the car somehow made the trip in reverse. In any case, car speedometers don't register negative speeds.

Also, you've posted here long enough that you should realize by now that your equation is written incorrectly.
240/s + 240/s+ 11 = 8
This means ##\frac{240}{s} + \frac{240}{s} + 11 = 8##

If the second fraction has s + 11 in the denominator, use parentheses to indicate that.

Also, do not just discard the homework template. Fair warning...
 
homework template?
 
When you start a thread in the homework section, it automatically contains a three part template. Possibly it doesn't if you have the PF app on a phone.
 
No, I was using taptalk, sorry, the next time I'll post using that instead. But anyway, back to the question, I've plugged both answers into the first equation, and get 8 when I plug in both numbers as possible answers, I realize that -6 is not a car speed, but sometimes in the homework, one answer won't work, but the other will satisfy, 55 should be a reasonable car speed, as could 66, depending on where this person lives, and what roads they were driving on. Is it asking me to if 55 were s, then add 11 to it and get both speeds?
 
Yes, I believe so. The form seems to be asking for s and s+11, the two speeds.
 
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