I am trying to help a friend with these in preparation for her final. This is a review study guide given to her.
Person X starts walking from point P at a rate of 8.6 ft/sec.
Sixty five seconds later Person Y starts jogging due south from point P at 7.4 ft/sec
At what rate is the distance between the two changing 13 minuets after Person Y begins jogging from point P?
I'm not sure what type of problem this would be or how to set it up? The 13 min seems like a red herring because they are both moving with constant speed. They are not accelerating or it would be in feet per second squared.
It's confusing all the way around... person X is walking faster then person Y is jogging and it seems more like a physics problem to me?
The second question:
An electronics store can sell 60 cellular phones per week at a price of $115. The manager estimates that for each $5 reduction in price she can sell 30 more phones per week. The phones cost the store $35 each. At what price should the store manager set the price so that she maximizes profit?
I dont know about that one either... I never did many calculus word problems.
I think this may involve an integral?