When faced with an unknown variable in a maths problem, it is advised to find the subject formula and then use it to solve the equation to find the answer.
<h3>What is an Unknown Variable?</h3>
This refers to the type of variable in a given equation that has to be solved for because its properties or value is not known.
Hence, we can see that when faced with an unknown variable in a given math problem, it is better to find the subject formula, then input the value of this into an equation, to find the value of the variable.
Read more about unknown variables here:
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Answer:The set fee would be $15
Explanation:The set fee is the starting value. This means that it is the value of the y at x = 0 (y-intercept).
To get the set fee, we would first need to get the equation of the line.
Equation of the linear line has the following general formula:
y = mx + c
where m is the slope and c is the y-intercept
1- getting the slope:we are given two points which are:
(20,25) and (50,40)
the slope =

The equation now is:
y = 0.5x + c
2- getting the value of the y-intercept:To get the value of the c, we will use any of the given points, substitute in the equation and solve for c.
I will choose the point (20,25)
y = 0.5x + c
25 = 0.5(20) + c
25 = 10 + c
c = 15
The equation of the line representing the scenario is:y = 0.5x + 15
Now, we know that the value of the c is the y-intercept which is the initial value of the function at x=0.
In our situation, this represents the set fee.
Hope this helps :)
The highest common multiple of 16 and 24 is 48.
3 x 16 = 48
2 x 24 = 48
The geometric sequence is a sequence in which the proceeding number is equal to the preceeding number multiplied by a ratio. The expression that represents this sequence is an = a1*r^(n-1) where r is the ratio and n is an integer. This type of formula is exponential
Answer:
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
That is z with a pvalue of
, so Z = 1.28.
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 7.6 - 0.1 = 7.5
The upper end of the interval is the sample mean added to M. So it is 7.6 + 0.1 = 7.7
The 80% confidence interval for the mean number of toys purchased each year is between 7.5 and 7.7 toys.