So mean is pretty easy to calculate; you just add everything up and divide by the number of things you added. Variance is pretty tricky because it involves subtracting the mean from each number, squaring that, adding all of the numbers up, and then dividing by the number of things. Then standard deviation is just the square root of the variance. Although some might enjoy spending hours figuring these out (I actually had to take a class where we only did this and stuff like it), most of us who use statistical tests do not want to waste our time on it. It is for that reason that there are websites that will compute all of these and all you have to do is put in the numbers. A pretty good one is:
http://www.calculator.net/standard-deviation-calculator.html
This one will calculate these and almost any other tests you need.
Now to your problem, if we add all of them up and divide by N (the # of things added), then we will get a mean of (μ=$5.10). From this, we can do further descriptive statistics. Standard Variance of the sample was calculated to (s^2=0.254). If we take the square root of the variance, we get a standard deviation of (s=0.504). I hope that this helps you with this problem and I hope that I helped for future problems by introducing the variance and standard deviation calculator to you!
Answer:
a>4 or a < 8
Step-by-step explanation:
We can start with the inequality on the left
-a + 2(4+3a) > 28
expand using the distributive property
-a + 8 + 6a > 28
5a + 8 > 28
subtract 8 from both sides to isolate the variable and its coefficient
5a > 20
divide both sides by 5 to isolate a
a > 4
moving on to the inequality on the right
2a - (3a+4) > -12
treat the minus sign as a -1
2a + (-1)(3a+4) > - 12
expand
2a - 3a - 4 > - 12
-a - 4 > -12
add 4 to both sides to isolate a and its coefficient
-a > - 8
multiply both sides by -1 but change the sign because we are multiplying by a negative number
a < 8
Answer:
circle b and it is bigger by 1 centimeter
Step-by-step explanation:
since circle b has a radius of 5 and radius is have of the diameter you have to do 5+5 to get the diameter when you do that you get 10 and then you have to subtract circle a diameter which is 9 from circle b diameter which is 10 so 10-9 is 1
Here, I think I can help you out:
1. 21 ÷ 3
= 7
Therefore, the length is 7cm².
2. 35 ÷ 7
= 5cm²
- And so on. Simply divide the area by the length of the side given; you can answer up to question six using this strategy.
7. All sides of a square are the same length.
7 x 7
= 49cm²
9. 2 x 3.5
= 7m²
- The formula to find the area of a square/rectangle is length x width. Just multiply the given lengths for the answers :)
