Answer:

Step-by-step explanation:
To find:
The value of
= ?
Solution:
Kindly consider the equilateral
as attached in the answer area.
Let the side of triangle =
units
Let us draw the perpendicular from vertex A to side BC.
It will divide the side BC in two equal parts.
i.e. BD = DC = 
Using Pythagorean Theorem in
:

Side AD = 
Using Trigonometric ratio:


Putting the values of AD and BD:

Answer:
A. 12.68 - 14.72 hours
B. Normal distribution.
Step-by-step explanation:
Part A
This question is using quantitative data. A 99% confidence interval means that you want to know the range where 99% of the population will be. To find this you have to convert the 99% CI into the z-score which is -2.58SD to + 2.58SD.
Note that the standard deviation(SD) is from the sample, not the population. We still need to find the standard deviation of the population. The formula is:
population SD = ![\frac{o}{\sqrt[]{n} }](https://tex.z-dn.net/?f=%5Cfrac%7Bo%7D%7B%5Csqrt%5B%5D%7Bn%7D%20%7D)
Where the o= sample SD = 7.4
n= number of sample = 463
The calculation will be:
population SD = ![\frac{o}{\sqrt[]{n} }](https://tex.z-dn.net/?f=%5Cfrac%7Bo%7D%7B%5Csqrt%5B%5D%7Bn%7D%20%7D)
population SD =
= 0.3951
The bottom limit will be:
Mean - SD * z-score= 13.7 - 0.3951*2.58 = 12.68 hours
The upper limit will be:
Mean + SD * z-score= 13.7 + 0.3951*2.58 =14.72 hours
The 99% CI range will be 12.68 - 14.72 hours
Part B
The table used to convert confidence interval into z-score depends on the distribution type of the data. Most data is classified as normal distributed, a data type that will concentrated at mean and spread equally from the mean. Normal distribution data will look like a bell which make it also called bell curve.
The question tells you that the data is normal distribution, but that doesn't mean every data is normally distributed. There are a lot of other data distribution type so we have to do some tests to know the normality of the data in real-life data.
Answer:
6) x = 11; y = 11
7) x = 9; y = 9
Step-by-step explanation:
Area of rectangle is width × length
which means area of rectangular floor in Tamara's room = width of room × length of room
-> 95 ⅚ sq feet = 8 ⅓ feet × length of
->(95 + 5/6) sq feet = (8 + 1/3) feet × length of room
->575/6 sq feet = 25/3 feet × length of room
length of room = (575/6)/(25/3)
= 575 × 3/6 × 25)
= 23/2
= 11 ½ feet