GK_Gmat wrote:

KillerSquirrel wrote:

20 miles race

time ---> no more then 20/8 = 2.5 hours

S+R = B-2 ---> in terms of time in hours.

lets assume R=0 so S+2 = B --->

S=~0 then B=~2

B cannot be less then two but --->S & R can !

so the answer is (D)

KS, I didn't get the logic behind this. Can you pls. explain?

Firstly why do we assume that R = 0?

Secondly, even if we do, and S + 2 = B, then how is S = ~0??

Finally, why can B not be less than 2?

Since you cannot have two first places, then one has to be first one has to be second and the last one has to be third.

you are being asked who

could have won the race ?

since you know that S+R = B-2 ---> Stephanie and Regine's combined times

exceeded Brian's time by exactly 2 hours.

than even if it took Stephanie no time (she run at the speed of light) to finish the race. then 0+R = B-2 ---> R = B-2

this still holdes that Stephanie and Regine's combined times

exceeded Brian's time by exactly 2 hours.

now lets assume that Regine came second (she run at the speed of sound) meaning also zero time but less the Stephanie.

0+0 = B-2 ---> B=2

still holds that Stephanie and Regine's combined times

exceeded Brian's time by exactly 2 hours.

so Brian is the only one that cannot win this race.

Even if you decide that Stephanie and Regine's time is one hour each then 1+1 = B-2 and B = 4 ---> B will always be slower then either R or S.

since the max speed for R,S or B is 20/8 = 2.5 then:

2.5+S = B-2

0.5+S = B

B is slower then S !!! by helf an hour and cannot win the race.