SOLUTION: Rui Feng and Jun wei represent their class in a 10 Km race. They started running at the same speed of x km/h .After 2Km , Rui Feng increased his speed by 1 Km/h and ran the remaini

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Question 1122393: Rui Feng and Jun wei represent their class in a 10 Km race. They started running at the same speed of x km/h .After 2Km , Rui Feng increased his speed by 1 Km/h and ran the remaining distance at a constant speed of (X=1) Km/h . Jun wei maintained his speed of X Km/h throughout the race.
1) Write down an expression in terms of X for the time taken by Rui Feng to complete the race.
2) Given that Rui Feng completed the race 40 Minutes earlier than Jun wei , formulate an equation in x and show taht it reduce to x^2+x-12=0.
3) Find the time taken by Rui Fng to complete the race, giving your answer in hours and minutes.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


1.

2.

Note that 40 minutes is hour. I'll let you do the reduction (hint, multiply through by ) and the solution of part 3 yourself.


John

My calculator said it, I believe it, that settles it