$A$ body covers half of its distance with speed $u$ and the other half with a speed $v$,the average speed of the body is

$A$ car moves from $X$ to $Y$ with a uniform speed $v_1$ and returns from $Y$ to $X$ with a uniform speed $v_2$. The average speed for this round trip is

An object moves with speeds $v_1, v_2$,and $v_3$ along line segments $AB, BC$,and $CD$ respectively,as shown in the figure. If $AB = BC$ and $AD = 3 AB$,then the average speed of the object will be:

$A$ bus travels the first one-third distance at a speed of $10\; km/h$,the next one-third at $20\; km/h$,and the last one-third at $60\; km/h$. The average speed of the bus is ........ $km/h$.

$A$ car starts from rest and moves such that it possesses average speeds of $5 \, ms^{-1}$,$10 \, ms^{-1}$,and $15 \, ms^{-1}$ in the first,second,and third seconds,respectively. What is the total distance covered by the car in these three seconds? ......... $m$

$A$ person travels $x$ distance with velocity $v_1$ and then $x$ distance with velocity $v_2$ in the same direction. The average velocity of the person is $v$. Then the relation between $v, v_1$ and $v_2$ will be: