Answer:
D) the spring has a length of 1 inch when no force is applied
Answer:
x=4
if that is what you need hope this helped
Step-by-step explanation:
This question is incomplete, the complete question is;
X and Y are independent Gaussian (Normal) random Variables. X has mean 13.9 and variance 5.2; Y has mean 6.9 and variance 3.8. . (a) Calculate P( W> 10)
Answer:
P( W> 10) is 0.1587
Step-by-step explanation:
Given that;
X ⇒ N( 13.9, 5.2 )
Y ⇒ N( 6.9, 3.8 )
W = X - Y
Therefore
E(W) = E(X) - E(Y)
= 13.9 - 6.9 = 7
Var(W) = Var(X) + Var(Y) -2COV(X.Y)
[ COV(X,Y) = 0 because they are independent]
Var(W) = 5.2 + 3.8 + 0
= 9
Therefore
W ⇒ N( 7, 9 )
so
P( W > 10 )
= 1 - P( W ≤ 10 )
= 1 - P( W-7 /3 ≤ 10-7 /3 )
= 1 - P( Z ≤ 1 ) [ Z = W-7 / 3 ⇒ N(0, 1) ]
from Standard normal distribution table, P( Z ≤ 1 ) = 0.8413
so
1 - P( Z ≤ 1 ) = 1 - 0.8413 = 0.1587
Therefore P( W> 10) is 0.1587
The 99% confidence interval for the true mean is given by:
where:
is the sample mean = 69.7
is the standard deviation = 2.8
is the test statistics = 2.58 for for 99% confidentce interval.
n is the sample size = 772.
Therefore, the 99% confidence interval is:
Answer:
To find a scale factor between two similar figures, find two corresponding sides and write the ratio of the two sides. If you begin with the smaller figure, your scale factor will be less than one. If you begin with the larger figure, your scale factor will be greater than one
