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wo persons A and B start from the opposite ends of a 450 km

two persons A and B start from the opposite ends of a 450 km straight track and run to and from between the two ends. The speed of the first person is 25 m/s and the speed of other is 35 m/s. They continue their motion for 10 hours. How many times did they pass each other? 
A. 1
B. 4
C. 3
D. 2

























Answer – D. 2Explanation :
First person speed = 25 m/s * 18/5 = 90 kmph
Second person speed = 35 m/s * 18/5 = 126 kmph
First person covers 90 * 10 = 900km
900/450 = 2
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