A race has three parts. The speed and time required to complete the individual parts for a runner is displayed on the following chart:Â Â Â Â Â Â Â Â Â Â Â Â _x005F_x000D_ Â Â Â Â Â Â Â Â Â Â Â Â Â Part IÂ Â Â Part IIÂ Â Â Â Part III_x005F_x000D_ Speed (kmph)Â Â Â Â 9Â Â Â Â Â Â 8Â Â Â Â Â Â Â 7.5_x005F_x000D_ Time (minutes)Â Â Â 50Â Â Â Â Â 80Â Â Â Â Â Â Â 100_x005F_x000D_ What is theÂ average speed of this runner?

A race has three parts. The speed and time required to complete the in

1.	A race has three parts. The speed and time required to complete the individual parts for a runner is displayed on the following chart:Â Â Â Â Â Â Â Â Â Â Â Â _x005F_x000D_ Â Â Â Â Â Â Â Â Â Â Â Â Â Part IÂ Â Â Part IIÂ Â Â Â Part III_x005F_x000D_ Speed (kmph)Â Â Â Â 9Â Â Â Â Â Â 8Â Â Â Â Â Â Â 7.5_x005F_x000D_ Time (minutes)Â Â Â 50Â Â Â Â Â 80Â Â Â Â Â Â Â 100_x005F_x000D_ What is theÂ average speed of this runner?
A.	8.17 kmph
B.	8.00 kmph
C.	7.80 kmph
D.	7.77 kmph
Answer» C. 7.80 kmph