Answer:
Confidence Interval in 95% confidence level for the quality rating is (6.06,7.46)
Step-by-step explanation:
Confidence Interval can be calculated using the formula M±ME where
- M is the mean of the sample
- ME is the margin of error in a given confidence level
Using the sample obtained from 50 business travelers we get
- Mean of the sample is 6.76
- standard deviation of the sample is 2.526
Margin of error (ME) around the mean using the formula
ME=
where
- z is the corresponding statistic in 95% confidence level (1.96)
- s is the standard deviation of the sample (2.526)
- N is the sample size (50)
Using the numbers in the formula we get:
ME=
≈ 0.70
Then the confidence interval becomes 6.76±0.70
Answer:
- ABCD is a rhombus, and a parallelogram
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<h3>Given </h3>
- Points A(-6, - 1), B(4, - 6), C(2, 5), D(- 8, 10)
First, plot the points (see attached picture).
Then, connect all the points.
<h3>We see that:</h3>
- Opposite sides are parallel,
- Diagonals are perpendicular.
From our observation the figure is rhombus.
Let's confirm it with the following.
1) Find midpoints of diagonals and compare.
- AC → x = (- 6 + 2)/2 = - 2, y = (- 1 + 5)/2 = 2
- BD → x = (4 - 8)/2 = - 2, y = (- 6 + 10)/2 = 2
The midpoint of both diagonals is same (- 2, 2).
2) Find slopes of diagonals and check if their product is -1, this will confirm they are perpendicular.
- m(AC) = (5 - (-1))/(2 - (-6)) = 6/8 = 3/4
- m(BD) = (10 - (-6))/(-8 - 4) = - 16/12 = - 4/3
- m(AC) × m(BD) = 3/4 * (- 4/3) = - 1
<u>Confirmed.</u>
So this is a rhombus and also a parallelogram but <u>not</u> rectangle or square, since opposite angles are not right angles.
Given vertices ofQuadrilateral RSTU as R(1,3), S(4,1), T(1,-3) and U(-2,-1).
We need to check if diagonals are congruent.
The coordinates of verticales diagonal RT are R(1,3) and T(1,-3).
The coordinates of verticales diagonal SU are S(4,1), and U(-2,-1),
By applying distance formula:

RT =
=
RT = 6
SU
.
.
Diagonal RT is not congruent to Diagonal SU.
Therefore, Quadrilateral RSTU is not a rectangle because the diagonals are not congruent.
So, it is False.
Answer:
c) they are screw lines
Step-by-step explanation:
A and B will intersect but never create a 90 degree angle. It comes at and angle smaller