Races and Games - General Questions

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 400 m race, A beats B by 40 m and B beats C by 20 m. By how many metres does A beat C?

In a 400 m race, A beats B by 100 m and B beats C by 10 m. By how many metres does A beat C?

A runs 1 1/4 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?

A runs 1 2/3 times as fast as B. If A gives B a start of x metres so that the race of 1000 m ends in a dead heat, what is x?