SOLUTION: Two cars start from the same point and travel in opposite directions with speeds of 45 and 60 miles per hour respectively. In how many hours will they be 490 miles apart? -Thanks a

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Two cars start from the same point and travel in opposite directions with speeds of 45 and 60 miles per hour respectively. In how many hours will they be 490 miles apart? -Thanks a      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 377563: Two cars start from the same point and travel in opposite directions with speeds of 45 and 60 miles per hour respectively. In how many hours will they be 490 miles apart? -Thanks a lot!
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

D = r*t OR D/r = t  BOTH cars will be traveling the same amountof time

Let x represent car's distance traveling at 45mph, 

and (490-x) the distance traveled by the car going 60mph

x%2F45+=+%28490-x%29%2F60

Cross multiply to solve

60x = 45(490-x)

60x = 45*490 - 45x

115x = 45*490

x = 45*490/105

x = 210mi, car's distance traveling at 45mph

210mi/45mph = 4 2/3 hours or 4hr and 40 min. 

CHECKING OUR ANSWER 

 210MI + 60mph*14/3hr = 210mi + 280mi = 490mi