Races and Games - General Questions

In a 100 m race, A beats B by 10 m and B beats C by 20 m. By how many metres does A beat C?

A runs 1 1/9 times as fast as B. If A gives B a start of x metres so that the race of 300 m ends in a dead heat, what is x?

In a game of 60 points, A can give B 15 points and B can give C 20 points. How many points can A give C?

A runs 1 2/3 times as fast as B. If A gives B a start of x metres so that the race of 500 m ends in a dead heat, what is x?

In a game of 80 points, A can give B 10 points and B can give C 20 points. How many points can A give C?