To solve this problem, you'll want to come up with an algebraic equation that represents how far both Molly & Mark have travelled. Once the distance they have traveled is the same, Mark will have caught up with Molly. We want to find out how many hours Molly had to drive to reach that distance, and we know that the time Molly has been driving is 2 hours longer than the time Mark has been driving.
I'd use the following equation.
x = number of hours Mark has been driving
45x = 27(x+2)
This equation shows the distance Mark has traveled (driving 45 miles per hour for x hours) equal to the distance Molly has traveled (driving 27 miles per hour for x+2 hours). Solving for x will give you the number of hours Mark traveled, but remember to add the 2 hours to that, because we know that Mark left after Molly had already been driving for two hours.
Molly left home and drove toward the ferry office at an average speed of 27 mph. Mark left two hours later and drove in the same direction but with an average speed of 45 mph. How long did Molly drive before Mark caught up?
I am terrible at word problems and this is a review question for a test. Can anyone help me? I have to solve it and write a statement.
4 answers
in 2 hours, Molly was 54 miles ahead.
Mark was going 18 mi/hr faster, so it took him 54/18 = 3 hours to catch up.
But 3 is not the answer to the question ...
Mark was going 18 mi/hr faster, so it took him 54/18 = 3 hours to catch up.
But 3 is not the answer to the question ...
Molly: d1=V*t = 27 * 2 = 54 Miles head-
start.
d2 = d1 + 54.
45*T = 27*T + 54
18T = 54.
T = 54/18 = 3 h.
start.
d2 = d1 + 54.
45*T = 27*T + 54
18T = 54.
T = 54/18 = 3 h.
Molly's Time = 3 + 2 = 5 h.
2 answers