Answer:
Length of segment PZ = 6 units
Step-by-step explanation:
As per theorem of intersecting chords in a circle ;
"Product of lengths of line segments on each chord are equal".
From the figure attached,
Chords XY and WZ are intersecting at point P in a circle.
By theorem; XP × PY = WP × PZ
7 × 12 = 14 × PZ
PZ =
PZ = 6 units
Therefore, length of the segment PZ = 6 units.
Answer:
The given data is:
x = (2, 7, 6, 10, 9, 13, 11, 18)
y = (11, 21, 12, 25, 7, 12, 4, 7)
a. The formula used for Sample Covariance is:
where, is mean of X
and is mean of Y
Firstly calculating . We get,
= 9.5
= 12.375
Now, Putting all values in above formula. We get,
Sample Covariance = -8.64
b. Standard Deviation is the square root of sum of square of the distance of observation from the mean.
where, is mean of the distribution.
Using formula we get,
Standard deviation = 4.81
c. Using above formula we get,
Standard deviation = 7.21
d. Correlation Coefficient is calculate by using formula:
where, = Covariance of X and Y
= Standard Deviation of X
= Standard Deviation of Y
Putting all values in above formula, we get,
Correlation Coefficient = -0.25
<em>Correlation Coefficient tell us that X and Y has negative week relationship whereas Sample Covariance tell us that X and Y has negative relationship. It does not tell us strength of relationship.</em>