Thursday, July 2, 2015

Speed (olympiad question. Via XL)

>
> bob is riding a bicycle at 15km per hour to his friend`s house a distance of 9km,
> unfortunately,his bicycle broke down and had to walk to there at 6km per hour
> he used 1 hour to reach there in total.
>
> QUESTION:What is the distance that he walked?
>
>
> NOTE:this is not impossible :)