Question
A cyclist rode for 4 hours at a constant speed of 'x' km/h
and then for 6 hours at a speed of (x - 10) km/h. If his average speed during the entire journey was 35 km/h, what is the value of 'x'?Solution
ATQ,
Distance covered in 4 hours = 4 × x = 4x km
Distance covered in 6 hours = 6 × (x - 10) = (6x - 60) km
Since, average speed = total distance ÷ total time
So, (4x + 6x - 60) ÷ (4 + 6) = 35
Or, 10x - 60 = 350
So, x = (350 + 60) ÷ 10
Or, x = 410 ÷ 10 = 41
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