Question 1091608
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On catching-up problems, see the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/word/travel/Typical-catching-up-Travel-and-Distance-problems.lesson>Travel and Distance problems for two bodies moving in the same direction (catching up)</A> 

in this site.



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This is how to solve this problem MENTALLY (without using equation).


<pre>
In 45 minutes Luis will be in {{{(3/4)*8}}} = 6 miles from the home.

So, the distance between him and Kristina was 6 miles when Kristina started her move.

Their relative speed is 28 - 8 = 20 mph.

It means that the distance between them increasing at the rate of 20 mph.

Hence, the time to catch up is {{{6/20}}} = {{{18/60}}} hours = 18 minutes.
</pre>

Solved.