To compute the mean, you simply have to sum all the elments in the data set and the divide the sum by the number of elements:

To compute the variance, we first need to compute the distance of each element from the mean. To do so, we build a "parallel" dataset, given by the difference of every value and the mean:


Now we need those difference squared:

The variance is the mean of this new vector, so

Finally, the standard deviation is simply the square root of the variance, so you have

To help you answer: think about what makes a fourth. If you have a rectangular cake, how do you split it into four pieces?
To do so with the compass however, remember that the joining the points of intersection of intersecting circles with the same radius creates a perpendicular bisector.
Answer:
12h4min
Step-by-step explanation:
39 + 25=64
1h=60mins
so 64/60=1 and the remain is 4.
4 is minute and 1 is hour
8 + 3 + 1=12hours
so The Answer is 12hours 4minutes
Answer:
21
Step-by-step explanation:
A parabolic function's key characteristic is either having 2 x-intercepts or 2 y-intercepts. That is the reason why the standard form of parabolic functions are:
(x-h)^2 = +/- 4a(y-k) or (y-k)^2 = +/- 4a(x-h), where
(h,k) is the coordinates of the vertex
4a is the lactus rectum
a is the distance from the focus to the vertex
This is also called vertex form because the vertex (h,k) is grouped according to their variable.
Since we don't know any of those parameters, we'll just have to graph the data points given as shown in the picture. From this data alone, we can see that the parabola has two x-intercepts, x=-4 and x=-2. Since it has 2 roots, the parabola is a quadratic equation. Its equation should be
y = (x+4)(x+2)
Expanding the right side
y = x²+4x+2x+8
y = x²+6x+8
Rearrange the equation such that all x terms are on one side of the equation
x²+6x+___=y-8+___
The blank is designated for the missing terms to complete the square. Through completing the squares method, you can express the left side of the equation into (x-h)² form. This is done by taking the middle term, dividing it by two, and squaring it. So, (6/2)²=9. Therefore, you put 9 to the 2 blanks. The equation is unchanged because you add 9 to both sides of the equation.
The final equation is
x²+6x+9=y-8+9
(x+3)²=y+1