i.e., in this race, A will win by $\left(5 min - 4 min 54 sec\right)$ = $\left(300 sec - 294 sec\right)$ = 6 sec

B covers 1000 m in 5 min

=> B covers 1000 m in 300 sec

$\text{=> B covers }\dfrac{1000}{300}= \dfrac{10}{3}\text{m in 1 sec}$

$\text{=> B covers }\dfrac{10}{3} \times 6 = 20\text{ m in 6 sec}$

i.e., A can give B a start of 20 metre so that the race will end in a dead heat.