SOLUTION: A car travels 20kph faster than a truck. The car covers 480km in two hours less than the time it takes the truck to travel the same distance. How fast does the car travel?
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-> SOLUTION: A car travels 20kph faster than a truck. The car covers 480km in two hours less than the time it takes the truck to travel the same distance. How fast does the car travel?
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Question 1167538: A car travels 20kph faster than a truck. The car covers 480km in two hours less than the time it takes the truck to travel the same distance. How fast does the car travel? Answer by ikleyn(52780) (Show Source):
You can put this solution on YOUR website! .
A car travels 20kph faster than a truck. The car covers 480km in two hours less than
the time it takes the truck to travel the same distance. How fast does the car travel?
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Let x be the rate of the car, in miles per hour.
Then the rate of the truck is (x-20) mph.
The time for the car to travel 480 km is hpurs.
The time for the truck to travel 480 km is hours.
The "time" equation is
- = 2 hours.
You can solve this equation mentally by easy guess the answer x= 80.
Indeed, - = - = 8 - 6 = 2 hours.
Alternatively, you can solve equation (1) algebraically.
If you do it this way your first step is to multiply both sides by x*(x-20).
ANSWER. The car's rate is 80 km/h.
