Y will equal 36. You can figure this out because you know y is double the value of x. If x is 18,you can just multiply it by 2, which equals 36
Answer:
The 80% confidence interval for the mean number of words a third grader can read per minute is between 40.4 wpm and 40.8 wpm.
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
.
So it is z with a pvalue of
, so 
Now, find 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 40.6 - 0.2 = 40.4 words per minute.
The upper end of the interval is the sample mean added to M. So it is 40.6 + 0.2 = 40.8 words per minute.
The 80% confidence interval for the mean number of words a third grader can read per minute is between 40.4 wpm and 40.8 wpm.
Answer:
78mm^2
Step-by-step explanation:
based on the information given, we can tell that the shape of the MP3 player is a rectangle. The formula for the surface area of a rectangle is SA=2WL+2LH+2HW
SA = Surface Area
W = Width
L = Length
H = Height
SA = 2(4)(7) + 2(7)(1) + 2(1)(4)
= 2(28) + 2(7) + 2(4)
= 56 + 14 + 8
= 78
Most linear systems you will encounter will have exactly one solution. However, it is possible that there are no solutions, or infinitely many. (It is not possible that there are exactly two solutions.) The word unique in this context means there is a solution, and it's the only one.
Hope this helps.