You drive from Albuquerque, NM, to Rock Springs, WY, at an average speed of 55 miles per hour?

This problem is in two parts. I could really use some help as to what I should be doing.



CONSTRUCT PROBLEM B USING THESE ELEMENTS



鈥? Calculate travel time. Account for layovers.



鈥? Travel by air from Memphis, TN, to Las Vegas, NV, with stops in Oklahoma City, OK, and El Paso, TX, en route.



鈥? Average aircraft groundspeed is 380 km/hour from Memphis to Oklahoma City and 310 km/hour from Oklahoma City to Las Vegas.







B. Construct a problem using the information from Problem B above. Assume that students will have a map of the United States that shows cities and a distance scale in kilometers. Require use of straight-line distance in kilometers for each leg of the trip.



1. Write a brief description of the process you used to construct the problem.



2. Write the steps you expect students to follow. Remember to include the calculations and the answers to each step.



3. Provide a scoring key with directions for its use and application. Include the answer ranges in the scoring key.You drive from Albuquerque, NM, to Rock Springs, WY, at an average speed of 55 miles per hour?
1) I examined the given conditions and noticed that the only additional information required to solve the problem was the layover time at each airport. I picked layover times of 1 hour 20 minutes for Oklahoma City and 1 hour 55 minutes for El Paso. I would then measure the 3 distances involved using the supplied map and ruler and from this calculate the travel times of each leg and added them to the layover times to arrive at the total travel time. Let's assume that I measured 690km for Memphis to Oklahoma City, 1169km from Oklahoma City to El Paso, and 941km from El Paso to Las Vegas.



2) I would expect them to accurately measure each of the 3 distances and convert them via the scale to kilometers. I would then expect them to divide those distances by the respective ground speeds to arrive at the travel times for each leg, i.e,



690km/(380km/hr) =~ 1.816hr (Memphis to Oklahoma City)

1169km/(310km/hr) =~ 3.771hr (Oklahoma City to El Paso)

941km/(310km/hr) =~ 3.035hr (El Paso to Las Vegas)



1.816hr + 3.771hr + 3.035hr = 8.622hr



To this sum I would expect them to add 3.250hr, the sum of the two layovers, to arrive at a final answer of 11.872hr.



3) I might score this problem as follows:



- Ruler measurements of each of the 3 map distances to within 5% of my measurements, 5% each for a total of 15%, partial credit possible if error not excessive.



- Correct conversion of measurement via scale to kilometers 5% each for a total of 15%



- Correct division of distance into speed 5% each leg for a total of 15%



- Correct addition of all 5 sums 25%, partial credit possible if error not excessive.



- Final answer within 5% of correct 30%, partial credit possible if error not excessive but over 5%



***** I tend to put the heaviest weight on the final answer, I don't know if your instructions differ -Gary*****