A can run 250m in 25 sec and B in 30 sec. How many metres start can A give to B in a km race so that the race may end in a dead-heat?

166.67 m

Distance covered by A in 25 seconds =  250 m

Distance covered by A in 100 seconds =  1 km

Similarly , 1 km Distance is  covered by B in = 120 sec

Distance covered by B in extra 20 seconds

= \(\frac{20}{120}\) × 1000 m

= \(\frac{20}{120}\) m

= 166.67 m

So, A beats B by 166.67 m.

For a dead-heat race, A must give B a start of 166.67 m.