A car is traveling south at a speed of 68 mi/h from Dallas toward San Antonio. Dallas is about 272 miles north of San Antonio. A truck is traveling north from San Antonio to Dallas at a speed of 71 mi/h. When and where will they pass each other?
1. Create a table to record the highway distance from San Antonio for 0-5 hours in one-hour intervals.
2. Graph the information in your table. Put time on the x-axis.3. What do the y-intercepts on your graph mean?
4. Where do the cars pass each other?
5. Which vehicle reaches its’ destination first?
Math - Reiny, Sunday, November 13, 2011 at 9:10pm
I will assume you meant to state that they left at the same time.
Let the distance covered by the southbound be x
let the distance covered by the northbound be 272-x
time for southbound = x/68
time for northbound = (272-x)/71
solve: x/68 = (272-x)/71
71x = 18496 - 68x
139x = 18496
x = 133.06
the southbound car went 133.06 , and the northbound went 138.94 miles when they met
time = 133.06/68 = 1.957 hrs
( check: 138.94/71 = 1.957 hrs )
Just follow the instructions for the remaining part of the question.