Question 457447
After x h the cars are 250 miles apart. After x h the first car travels 30*x miles

and the second car travels 45*x miles. Since the cars after x h are 250 miles 

apart we write:{{{45*x+30*x=250}}}=>{{{75x=250}}}=>{{{x=3&1/3}}}h

Answer:After 3 h and 20 min the cars are 250 miles apart.