The answer should have been 8.6 that was wrong but it is okay you were close
The correct answer is A. 1
Answer:
![Average\ Speed = \frac{s(7) - s(2)}{5}](https://tex.z-dn.net/?f=Average%5C%20Speed%20%3D%20%5Cfrac%7Bs%287%29%20-%20s%282%29%7D%7B5%7D)
Step-by-step explanation:
Given
t = 2 to 7
Required
Find the average speed over these intervals
The function is not given; so, I'll represent the function as s(t)
When ![t = 2;](https://tex.z-dn.net/?f=t%20%3D%202%3B)
![s(t)= s(2)](https://tex.z-dn.net/?f=s%28t%29%3D%20s%282%29)
When ![t = 7](https://tex.z-dn.net/?f=t%20%3D%207)
![s(t) = s(7)](https://tex.z-dn.net/?f=s%28t%29%20%3D%20s%287%29)
![Average\ Speed = \frac{Change\ in\ Distance}{Change\ in\ Time}](https://tex.z-dn.net/?f=Average%5C%20Speed%20%3D%20%5Cfrac%7BChange%5C%20in%5C%20Distance%7D%7BChange%5C%20in%5C%20Time%7D)
This gives:
![Average\ Speed = \frac{s(7) - s(2)}{7 - 2}](https://tex.z-dn.net/?f=Average%5C%20Speed%20%3D%20%5Cfrac%7Bs%287%29%20-%20s%282%29%7D%7B7%20-%202%7D)
![Average\ Speed = \frac{s(7) - s(2)}{5}](https://tex.z-dn.net/?f=Average%5C%20Speed%20%3D%20%5Cfrac%7Bs%287%29%20-%20s%282%29%7D%7B5%7D)
Plus a negative value becomes subtraction:
-12 + -23 = -12 -23 = -35
40%=0.4
0.4+1=1.4
4.5(1.4)=6.3
The answer is $6.30