a person covers equal half distance at speed V and remaining half at speed V1 and V2 in equal interval of time .find average speed.

Average speed = ( 2V + V1 + V2)/4

Explanation:

Given that a person covers equal half distance at speed V and remaining half at speed V1 and V2 in equal interval of time .find average speed.

Since the distance is covered at equal intervals of time, and

Speed = distance/time

For the first half distance,

V = distance/t

Cross multiply

Distance = Vt

For the second half distance

(V1 + V2)/2 = distance/t

Distance = t(V1 + V2)/2

The average speed = total distance/ total time.

Average speed = [Vt + t( V1 + V2)/2] ÷ 2t

Average speed = (2Vt + V1t + V2t)/4t

Average speed = t( 2V + V1 + V2)/4t

Time t will cancel out

Average speed = ( 2V + V1 + V2)/4

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