From each of two normal populations with identical means and with standard deviations of 6.40 and 7.20, independent random samples of 64 observations are drawn. Find the probability that the difference between the means of the samples exceeds 0.6 in absolute value. math. stackexchange

0.31207

Step-by-step explanation: from the question, the distribution follows a normal distribution and population mean of both data set are equal.

I will also assume a 5% level of significance since any level of significance was not given in the question.

Population standard deviation of the first population (σ1) = 6.40

Population variance of the first population (σ1)² = 40.96

Population standard deviation of the second population (σ2) = 7.20

Population variance of the second population (σ2)² = 51.84

Sample size of first population (n1) = 64

Sample size of second population (n2) = 64

Difference between sample mean (x1 - x2) = 0.6.

Since population standard deviation is known, z test is used in getting the z score and a normal distribution table is used in getting the probability attached to the z score.

Z = (x1 - x2) /√{(σ1)²/n1 + (σ2)²/n2}

By substituting parameters, we have

Z = 0.6/√(40.96/64) + (51.84/64)

Z = 0.6/ √0.64 + 0.81

Z = 0.6/√1.45

Z = 0.6/1.2041

Z = 0.49

Since our difference in sample mean is greater than zero, it means that the probability of the z score (z=0.49) must be that of the one greater than 0.49 which is area towards the right of the distribution.

Do note that the probability value under z score to the left + probability value under z score to the right = 1

The table I'm using here is only giving probability of z scores toward the left (z<0.49)

Hence z>0.49 = 1 - z<0.49

From the table, z<0.49 = 0.68793

z>0.49 = 1 - 0.68793

z>0.49 = 0.31207

the answer is b: 18

step-by-step explanation:

use the pythagorean theorem to .

a^2+b^2=c^2

plug 18 for "r"

the 2 legs are 18 and 24

18^2+24^2=c^2

324+576=c^2

900=c^2

c=30

30-12=18

18 is the radius

: )

d

step-by-step explanation:

the 2000 florida legislature amended section 322.05, florida statutes, changing the requirements to obtain a class e license for a driver under the age of 18 holding a learner's license. the following requirements must be met in order to obtain a regular class e license if a learner's license is issued on or after october 1, 2000:

must hold a learner's license for at least 12 months or until the 18th birthday.

must have no convictions 12 months from the issue date of the learner's license.

may have one traffic conviction within 12 months from the issue date of the learner's license if adjudication is withheld.

a parent, legal guardian, or responsible adult over 21 years old must certify that the driver has 50 hours driving experience, including 10 hours of night time driving.