SOLUTION: John leaves home at 9 am and walks 4 mph. His brother Greg, leaves half an hour later and runs 8.5 mph in the same direction. Predict the time at which Greg will catch up to John.

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: John leaves home at 9 am and walks 4 mph. His brother Greg, leaves half an hour later and runs 8.5 mph in the same direction. Predict the time at which Greg will catch up to John.       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1126913: John leaves home at 9 am and walks 4 mph. His brother Greg, leaves half an hour later and runs 8.5 mph in the same direction. Predict the time at which Greg will catch up to John. How do you solve this?
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
How MUCH time Greg traveled, x

4%28x%2B0.5%29=8.5%2Ax
x=%284%2F9%29%2Ahours
About 9:27 AM, when Greg catches up


Upon catchup , each traveled the same distance,
          SPEED      TIME QUANTITY      DISTANCE

JOHN       4         x+0.5               4(x+0.5)

GREG       8.5         x                 8.5x

Equate the two distance expressions.
Solve for x.
Apply x to the given time.