Answer:

Step-by-step explanation:
the mean is given by:

In our case this is:

side note: the main difference between sample mean and population mean is in the 'context'. However, the method to calculate them is the same.
By context I mean: if this the items are taken from some larger category for example: the ages of a few 'students' from a 'class'. Here 'students' are the sample from a larger set that is 'class'. The mean of the 'few students' will be called sample mean. In contrast, if we take the mean of the ages of the whole class then this is called population mean. (population mean == mean of the whole set)
In our case we aren't told exactly where these numbers come from, is this the whole set or a sample from it, the lack of context allows us to assume that the mean can either be population mean or sample mean. So we can safely use any symbol
or
.
Answer:
what topic???????????????????
X equals 60 degrees (80-20=60)
Answer:
y = 2.31x + 309.35
Step-by-step explanation:
Whenever you are checking for a best fitting equation you want to check if it has a constant slope. If it does then the relation is linear and super easy.
So, since the t values are increasing by the same amount you want to see if the y values are too. And they are, each population entry is increasing by 2.31, this is the slope.
Also, keep in mind you can caluclate slope with the equation
here x is replaced by t though.
Now, since we know it's linear and we know the slope we can find the equation with the formula y - y1 = m(x - x1) where again, x is replaced by t and m is the slope 2.31
I am just going to use the first point. so x1 = t1 = 0
y - 309.35 = 2.31(x-0)
y = 2.31x + 309.35
Let me know if there was something you didn't understand.