Question
A biker travels first half of his journey with a speed
of 18 km/h and the other half with a speed of 'x' km/h. If the total distance traveled by him is 180 km and the total time taken is 10 hours, then find the value of 'x'.Solution
ATQ, When the same distance is traveled in two parts, the average speed is given by Average speed= {2xy/(x+y)}, where 'x' and 'y' are the speeds. Average speed of biker = [(2×18×x)/(x+18)] 
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