Question 1106772
 In a Grand Prix automobile race with five different race cars,
 Rapid Ravi averaged 90 mi/hr for the first half of the course and 110 mi/hr for the second half of the course.
 Steady Spencer maintained a constant speed of 100 mi/hr throughout the race.
 They were the only two cars to complete the race.
 Who won the race? How much did the winner win by?
:
let d = the distance of half the race
Find the total time of R, (time = dist/speed)
{{d/90}}} + {{{d/110}}}
Common denominator is 990
{{{(11d + 9d)/990}}} = {{{(20d)/990}}}
simplifies to
{{{(2d)/99}}} = the time of R
:
Find the time of S
{{{(2d)/100}}} is S's time and so he wins the race.
:
"How much did the winner win by?:
they don't give the length of the race track, no. of laps, etc
Assuming they use the 2 hr rule
S travels 2 * 100 = 200 mi
R travels 2 * 99  = 198 mi
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winner wins by: 2 mi