As I was completing the homework, I noticed I was having trouble with rates / work problems. The main problems I am having is determining time when the problems relate to being slower/faster, left....and met/arrived. Also, when I complete the practice problems I also seem to have difficulty in remembering when to add times and distances, because there are some scenarios where you do have to add time / distances, and others where the results vary.

For my first concern, an example problem which I had a difficulty in determining t was chapter 2 ( Word Translations, 4th edition, page 38).

Stacy and Heather are 20 miles apart and walk towards each other along the same route. Stacy walks at a constant rate that is 1 mile per hour faster than Heather's constant rate of 5 miles/hour. If Heather starts her journey 24 minutes after Stacy, how far from her original destination has Heather walked when the two meet?

Originally when I set my RTD table, I gave Heather the constraints of (t + 0.4). However, in the explanation it lists Stacy as having that equation for t. I think I kept it as (t+0.4) for Heather because the question states " Heather starts her journey 24 minutes after Stacy." But I am still unclear about why it should not be written like this for Heather.

For the second concern, I am constantly referring back to the examples when trying to complete the in action problems as I am unable to conceptualize which columns to add when.

I would greatly appreciate any advice or clarifications you may have regarding this.

I completely understand! This is tricky stuff. By giving Heather "t+.4" to represent Heather's time walked and Stacy "t" to represent Stacy's time walked, you are saying that Heather walked an extra .4 hours. In fact, it was Stacy who walked the longer amount of time!

I find this confusing too, so here's what I do: I always decide who left later. That person get "t" to designate his/her time. Then whoever left *earlier* gets the "t + (extra time)" to show that that person actually moved for a longer period of time. Does this help?

_________________ Jamie Nelson ManhattanGMAT Instructor

Yes! That definitely helps to clarify how to interpret these types of questions. Thank you!

Glad to hear it! My pleasure!

_________________ Jamie Nelson ManhattanGMAT Instructor

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