$A$ train starts from Delhi on Sunday at $9 \, am$ with a speed of $25 \, km/h$. Another train starts from the same place on the same day at $3 \, pm$ with a speed of $40 \, km/h$ in the same direction. Find at what distance from Delhi both trains will meet? (in $km$)

$A$ boy started from his house by bicycle at $10:00\, a.m.$ at a speed of $12\, km/hr$. His elder brother started after $1\, hr\, 15\, mins$ by scooter along the same path and caught him at $1:30\, p.m.$ The speed of the scooter will be (in $km/hr$):

$A$ man walks at the rate of $5 \, km/hr$ for $6 \, hours$ and at $4 \, km/hr$ for $12 \, hours$. The average speed of the man (in $km/hr$) is:

Seeta and Geeta cycled towards each other,one from point $A$ and the other from point $B$,respectively. Seeta left point $A$ $6 \, hours$ later than Geeta left point $B$,and it turned out on their meeting that Seeta had travelled $12 \, km$ less than Geeta. After their meeting,they kept cycling with the same speed,and Seeta arrived at $B$ $8 \, hours$ later and Geeta arrived at $A$ $9 \, hours$ later. Find the speed of the faster cyclist in $km/hr$.

$A$ man driving at $\frac{3}{4}$ of his original speed reaches his destination $20 \text{ minutes}$ later than the usual time. Then the usual time is (in $\text{minutes}$)

Two trains of equal length take $10 \, s$ and $15 \, s$ respectively to cross a telegraph post. If the length of each train is $120 \, m$,in what time (in $s$) will they cross each other while travelling in the same direction?