Question

A scooterist complete a certain distance in 10 hours. he covers half the distance at 30 km/h and rest at 70 kn/h . what is the total distance cover in journey

Answer 1

Motion,

Given that,
The total time taken by a scooterist to complete a certain distance = 10 hr.

Let the total distance of the path = x km
and the time taken to go ½ of the distance at 30 km/hr = y hr.

So, 30 × y = ½ × x
or, y = x/60 hr.

Also the time taken to go the rest of the journey at 70 km/hr = z

So, 70 × z = ½ × x
or, z = x/140 hr.

According to this
y + z = 10
or, x/60 + x/140 = 10
or, x(1/60 + 1/140) = 10
or, x{(140 + 60)/60×140} = 10
or, x(200/8400) = 10
or, x (1/42) = 10
or, x = 420 km.

Therefore the total distance covered in the journey is 420 km.

That's it
Hope it helped (≧∇≦)b