a. The formula for speed is: distance = speed*time
Solved for time, the formula is: time = distance/speed
time that each animal went was:
Cheetah = L/113
Falcon = L/161
Sailfish = L/105
To find the average speed, we need to divide the total distance traveled by the total time that was used.
vav = Distance total/Time total
vav = (L + L + L)/(L/113 + L/161 + L/105)
vav = 3L/(16,905L/1,910,265 + 11,865L/1,910,265 +18,193L/1,910,265)
vav = 3L/(46,963L/1,910,265)
vav = 3L(1,910,265)/46,963L
vav = 122.1 km/h
b. To find the numerical average of the 3 speeds, just add the speeds together and divide by 3
(113 + 161 + 105)/3
To compare the two, we need to make a ratio: 122.1/129.7
This approximates to .941.
c. The reason that these numbers are not the same is that the animals did not spend the same time in each leg of the relay. The average velocity is a ratio of distance covered to time spent covering it. Since the animals each spent a different amount of time in their leg of the race, the speed of each animal factored differently into the average speed of the team.