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.