If we assume that the number of trucks on the highway is t, the number of cars on the highway will be 2*t = 2t

The total number of cars and trucks on the road is 2t+t= 300

The number of vehicles on the road is 3t=300

The are t=300/3 trucks on the highway.

This means there are t=<<100=100>>100 trucks on the road.

# Answer

100
<|im_start|>system
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<|im_start|>user
On a highway, the total number of vehicles passing is 300. If the number of cars on the highway is twice the number of trucks, find out the total number of trucks on the highway?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
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user
100
On a highway, the total number of vehicles passing is 300. If the number of cars on the highway is twice the number of trucks, find out the total number of trucks on the highway?
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