Answer: 0.82 miles per gallon
Step-by-step explanation:
Given : Jenna has bought a new hybrid car. Each week for a period of seven weeks, she has noted the fuel efficiency (x) (in miles per gallon) of her car.
The results are :45 44 43 44 45 44 43
The formula to find the standard deviation is given by :-

First we find mean of the given data ,

Now,


Now, standard deviation of the above results will be :-

Hence, the standard deviation of these results = 0.82 miles per gallon
8 2/3
because 6 1/2 divided by 3/4 is 8 2/3
Answer:
the second one
Step-by-step explanation:
Answer:
y = -2x^2 - 4x - 1
Step-by-step explanation:
We can see that the graph passes through (-2, -1), (-1, 1) and (0, -1).
Let's solve
ax^2 + bx + c = y
a(-2)^2 + b(-2) + c = -1
4a - 2b + c = -1
a(-1)^2 + b(-1) + c = 1
a - b + c = 1
a0^2 + b0 + c = -1
c = -1
we got c = -1 so we input it into the other 2
4a - 2b - 1 = -1
4a - 2b = 0
2a - b = 0
2a = b
a - b - 1 = 1
a - b = 2
a = b + 2
Let's input b = 2a
a = 2a + 2
-a = 2
a = -2
b = 2a = 2*(-2) = -4
c = -1
y = -2x^2 - 4x - 1
the formula for the Pythagorean theorem is a squared plus b squared is equals to c squared we don't have our a so it will be 8 * 8 =64which is 64 is equals to 10 * 10 which is 100 - 64 is equals to 36 then you square root do square roots the 36 which is 6