SOLUTION: Solve: The amount of time it takes a swimmer to swim a race is inversely proportional to the average speed of the swimmer. A swimmer finishes a race in 75 seconds with an averag

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Solve: The amount of time it takes a swimmer to swim a race is inversely proportional to the average speed of the swimmer. A swimmer finishes a race in 75 seconds with an averag      Log On


   

Question 144495: Solve:
The amount of time it takes a swimmer to swim a race is inversely proportional to the average speed of the swimmer. A swimmer finishes a race in 75 seconds with an average speed of 4 feet per second. Find the average speed of a swimmer if it takes 60 seconds to finish the race.
Found 2 solutions by jojo14344, amalm06:
Answer by jojo14344(1513) About Me  (Show Source):
You can put this solution on YOUR website!
Okay, being inv.proportional meaning when time (T1) decrease in time (T2), so speed (S1) will go up in speed (S2). It's inv.proportional! To show,
(T1)(S1) = (T2)(S2) ----- eqn 1
We're looking for speed (S2) right, so substituting,
(75)(4) = (60)(S2)
S2=(300/60)
S2= 5ft/sec. This is his speed in 60 seconds.
It's just right because time1 decrease to time2, so speed1 will increase to speed2...being inversely proportional.
Thank you,
Jojo

Answer by amalm06(224) About Me  (Show Source):
You can put this solution on YOUR website!
t=k(1/v), where k is some constant of proportionality
k=tv=75*4=300
v=k/t=300/60=5 ft/s (Answer)