In a km race A can give B 50 m start and B can give C 40 m start. What start can A give C in a 2 km race?

∵ B runs 1000 m while C 960 m
∴ B runs 995 m while C 960 * 995 / 1000 = 912 m
Now, A runs 1000 m while C 960 m
∴ A runs 2000 m while C 2000 * 912 / 1000 = 1824 m
Hence, A can give C (2000 – 1824) = 176 m start.