Question 1077070
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Formally, the necessary and the sufficient condition is this: "the car B must move at the speed higher than the car A".


And if the condition is in place and if the two cars move for a sufficiently long time, then the car B INEVITABLY will catch up the car A.



If you want to learn MORE about solving "catching-up" problems, read 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.