SOLUTION: A sprinter who average 30ft/sec. completed a race 1 sec before another sprinter who average 28ft/sec.What was the distance of the race.

Question 144194: A sprinter who average 30ft/sec. completed a race 1 sec before another sprinter who average 28ft/sec.What was the distance of the race.
Found 2 solutions by ankor@dixie-net.com, scott8148:
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
A sprinter who average 30ft/sec. completed a race 1 sec before another sprinter who average 28ft/sec.What was the distance of the race.
:
Find the time of of the 1st sprinter first
Let t = time of the 1st runner to complete the race
then
(t+1) = time of the 2nd runner
:
Write a distance equation
:
Distance = speed * time
:
1st runner dist = 2nd runner dist
30t = 28(t+1)
30t = 28t + 28
30t - 28t = 28
2t = 28
t =
t = 14 sec time of the 1st runner
;
Then, we know dist = speed * time
30 = 14 = 420 ft
:
Check solution using the 2nd runner who took 1 sec longer
28 * 15 = 420 ft
Answer by scott8148(6628) (Show Source): You can put this solution on YOUR website!
if the winner won by 1sec, he also won by 28ft; because the second sprinter ran 28ft/sec

the difference in their speeds was 2ft/sec; so to get a 28ft lead, the winner must have run for 14sec (28/2)

30ft/sec for 14sec is 420ft (140yd)

using equations __ let x=distance __ d=rt __ t=d/r

x/28=(x/30)+1 __ multiplying by 420 (LCM) __ 15x=14x+420 __ x=420
RELATED QUESTIONS
A sprinter who averaged 30ft/sec completed a race one second before another sprinter who... (answered by stanbon)
1.A sprinter who average 30 ft/sec completed a race 1 sec before another sprinter who... (answered by stanbon)
a sprinter has a bad start and his opponent is able to start 1 second before him if the... (answered by edjones)
A bicycle completed the first 438.7 m of a ride in 174.57 sec. What was the bicycle's... (answered by mananth,josgarithmetic)
Sprinter A runs 100 meters in 15 seconds, while sprinter B starts 1.5 seconds later and... (answered by ankor@dixie-net.com)
Track: Sprinter A runs 100 meters in 15 seconds, while sprinter B starts 1.5 seconds... (answered by ankor@dixie-net.com)
Sprinter A runs 100 meter in 15seconds, while sprinter B starts 1.5 second later and runs (answered by TimothyLamb)
Sprinter A runs 100 meters in 15 seconds, while sprinter B starts 1.5 seconds later and... (answered by TimothyLamb)
a sprinter has a bad start and his oponent is able to start 1 second before him. if the... (answered by stanbon)