SOLUTION: A car travels 20 kilometers faster than a truck per hour. The car covers 350 kilometers in two hours less than the time it takes the truck to travel the same distance. What is the

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Question 1184721: A car travels 20 kilometers faster than a truck per hour. The car covers 350 kilometers in two hours less than the time it takes the truck to travel the same distance. What is the speed of the car and the truck?



Answer by ikleyn(52847) About Me  (Show Source):
You can put this solution on YOUR website!
.
A car travels 20 kilometers faster than a truck per hour.
The car covers 350 kilometers in two hours less than the time it takes the truck to travel the same distance.
What is the speed of the car and the truck?
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Let's the slower speed be r km/h;  then the faster speed is  (r+20) km/h.


The time equation is then


    350%2Fr - 350%2F%28r%2B20%29 = 2  hours.



As soon as  you wrote this equation, you can solve it formally,

but also can to guess the solution MENTALLY, in your mind:  r = 50 km/h.



ANSWER.  The truck' speed is 50 km/h.  The car' speed is  50+20 = 70 km/h.



CHECK.  350%2F50 - 350%2F%2850%2B20%29 = 7 - 5 = 2 hours, exactly as the problem states.


Solved.