Answer: The mean of the data is 433.75, variance of the data is 99667.19 and the standard deviation of the data is 315.7011.
Explanation:
The given data is 900, 35, 500 and 300.
The number of observation is 4.
Formula of mean is,


The formula of variance is given below,



The variance of the data is 99667.19


The standard deviation of the data is 315.7011.
The other information or values of given chart is shown in the attached table.
<span> ; 112 jumps</span><span> ; 128 jumps</span><span> ; 151 jumps</span><span> ; 172 jumps
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a. The first variable is x and the second variable is y.
b. The equations are
and 
Step-by-step explanation:
Step 1:
The first step is to define the variables. The variables can be any two symbols, letters, characters, etc.
Here let the first variable be x and the let the second variable be y.
So the variables are defined as x and y.
Step 2:
The sum of the given variables is 12.
The first variable + the second variable = 12,

The difference between the two variables is 4.
The first variable - the second variable = 4.

Step 3:
If we add both the equations we get,
and 
x = 8 and y = 4.
Answer:
Step-by-step explanation:
cant help when you put question marks!
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