Answer:
(a) The sample variance is 16.51
(a) The sample standard deviation is 4.06
Step-by-step explanation:
Given

Solving (a); The sample variance.
First, calculate the class midpoints.
This is the mean of the intervals.
i.e.





So, the table becomes:

Next, calculate the mean




Next, the sample variance is:

So, we have:



The sample standard deviation is:



Answer:
0.25
Step-by-step explanation:
1. Add up all of the students.
20+20+25+7+13+5+3+2+5=100
2. Make a ratio of that number and the number of all the students in Music/Drama
MUSIC/DRAMA: 7+13+5=25

3. Simplify
= 0.25
The formula to find the surface area of a sphere is A=4(3.14)r². So if you plug in the data you would get,
A=4(3.14)4²
A=(12.56) (16)
A=200.96
You mught want to check over it so you will be able to solve it for yourself the next time you have this question.
6.4x + 2.8y = 44.4
6.4(3) + 2.8y = 44.4
19.2 + 2.8y = 44.4
-19.2 -19.2
2.8y = 25.2
------ ------
2.8 2.8
y = 9
Answer:
<h2>(8, -22)</h2>
Step-by-step explanation:
The slope-intercept form of an equation of a line:

m - slope
b - y-intercept
The formula of a slope:

First table:
(-4, 26), (0, 10) → b = 10


Second table:
(-4, 14), (0, 2) → b = 2


We have the system of equations:
