Question

A car travels at 40 km/h for the first third of its journey , 35 km /hfor the second third of its journey and 42 km/h for the final third of its journey. What is its average speed?


answer fast
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Answer 1

Speed(s)=distance(d)/time(t)

Let us assume the total distance travelled to be 3x.

So the car travels x distance with each speed.

Since, s=d/t,

t=d/s

So the total time taken would be

T=x/40 + x/50 + x/60

Total distance, D=3x

Avg speed = D/T = 3x/( x/40 + x/50 + x/60 )

Cancel x from numerator and denominator and solve for average speed.

Answer 2

Hey Mate,

First third speed=40 km/h

Second third speed=35 km/h

Final third speed=42 km/h

Average={(40+35+42)÷3}

=117÷3

=39 km/h

Hope it helped you.

Please mark my answer as brainliest.