Question 1091555
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<pre>
Let x be the Coleen' speed, in miles per hour.

Then Mariah travels at the speed (x+9) mph.


The equation is

3x + 3*(x+9) = 81,

and it says that the two covered the total distance of 81 miles in 3 hours, moving toward each other.


Simplify and solve for x:

3x + 3x + 27 = 81,

6x = 81 - 27 = 54  ====>  x = {{{54/6}}} = 9 mph.


<U>Answer</U>.  Coleen' speed is 9 mph;  Mariah' speed is 9 + 9 = 18 mph.
</pre>

Solved.



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&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/travel/Travel-and-Distance-problems-for-two-bodies-moving-toward-each-other.lesson>Travel and Distance problems for two bodies moving in opposite directions</A> 

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