SOLUTION: Please, I have had a real problem figuring out this one. it is a weighted average. At 7am Brooke leaves home to go on a business trip driving 35mph. 15 minutes later Bart discov

Algebra ->  Average -> SOLUTION: Please, I have had a real problem figuring out this one. it is a weighted average. At 7am Brooke leaves home to go on a business trip driving 35mph. 15 minutes later Bart discov      Log On


   

Question 30304: Please, I have had a real problem figuring out this one. it is a weighted average. At 7am Brooke leaves home to go on a business trip driving 35mph. 15 minutes later Bart discovers that she forgot her materials. He drives 50mph to catch up with her. Bart is delayed 30 minutes with a flat tire. When will he catch up with Brooke? I really don't understand how the 1/2 hour figures in or how to calculate the speed to catch up......HELP!
Answer by Paul(988) About Me  (Show Source):
You can put this solution on YOUR website!
Let the time be x


15 minutes = 0.25hours

30 minutes = 0.5hours

Equation:







35x+8.75=50x-25

15x=33.75

x=2.25





Hence, it will take him 2.25 hours to catch up to her.

Paul.