SOLUTION: Two cars are headed directly toward each other at rates of 20 mph and 80 mph. How many miles apart are they 2 min before impact?

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Two cars are headed directly toward each other at rates of 20 mph and 80 mph. How many miles apart are they 2 min before impact?       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 653017: Two cars are headed directly toward each other at rates of 20 mph and 80 mph. How many miles apart are they 2 min before impact?









Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Two cars are headed directly toward each other at rates of 20 mph and 80 mph. How many miles apart are they 2 min before impact? 
They're approaching each other at 20+80 or 100 miles per hour, or 100 miles per
60 minutes, or 10 miles per 6 minutes, or 5 miles per 3 minutes, 2/3 of 5 miles
in 2/3 of 3 minutes which is 2 minutes.  And 2/3 of 5 miles is 10/3 or 3 1/3
miles.


Or you can make this table, using 2 minutes as 2/60 or 1/30th of an hour.

             Rate ×  Time  = Distance 
Slow car      20     1/30      2/3
Fast car      80     1/30      8/3
-----------------------------------
                      Total = 10/3 = 3 1/3 miles

Edwin