Answer: You need to show the number line in order to get an answer.
This may be the right answer: x=-1 y=-11/5
Answer:
a) The formula is given by mean 
the margin of error. Where the margin of error is the product between the critical value from the normal standard distribution at the confidence level selected and the standard deviation for the sample mean.
b) 
Step-by-step explanation:
Previous concepts
A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".
The margin of error is the range of values below and above the sample statistic in a confidence interval.
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
If the distribution for X is normal or if the sample size is large enough we know that the distribution for the sample mean 
is given by:
Part a
The formula is given by mean the margin of error. Where the margin of error is the product between the critical value from the normal standard distribution at the confidence level selected and the standard deviation for the sample mean.
Part b
The confidence interval for the mean is given by the following formula:
Answer:
12.5% increase OR 112.5% Percentage of Change
Step-by-step explanation:
For this problem consider that our original maximum value is 96 square feet, but our new maximum value is 108 square feet. So to find the change as a percentage (in this case the increase) use the following formula:
Percentage of Change = ( New Maximum / Old Maximum ) * 100
So, let's use this formula to find the percentage change of the room.
Percentage of Change = ( 108 / 96 ) * 100
Percentage of Change = (1.125) * 100
Percentage of Change = 112.5
So the percentage of Change is 112.5%. Note, the old maximum is the point of comparison which is 100%.
So to find the increase, we will do 112.5% - 100% to get 12.5%. Hence, we have a 12.5% increase of a 108 square foot room compared to a room of 96 square feet.
Cheers.
