1. A population with a normal distribution has a mean of 104 and standard deviation 15. A sample of 30 items is taken from that population. (a) (4 points) What is the probability of the sample mean being not less than 103?

0.3575

Step-by-step explanation:

A population with a normal distribution has a mean of 104 and a standard deviation of 15. A sample of 30 items is taken from that population. (a) (4 points) What is the probability of the sample mean is not less than 103?

The probability of the sample mean is not less than 103 means the sample mean is equal to 103

We solve using the z score formula

z = (x-μ)/σ/√n

where

x is the raw score = 103

μ is the population mean = 104

σ is the population standard deviation = 15

n is the random number of sample = 30

z = 103 - 104/15/√30

z = -1/2.7386127875

z = -0.36515

Probability value from Z-Table:

P(x≤ 103) = 0.3575

Therefore, the probability of the sample mean is not less than 103 is 0.3575

i think it is everything has to equal 180 so, if i correct 4=c. 6=d. 8=a. 7=b. and the last question would be c. because they are parallel lines and they are congruent.

step-by-step explanation:

the reason everything has to equal to 180 is because that is how it works. i'm guessing that is its rule. 4 and 8 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 6 and 7 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 60+60 is 180. so, now you have your answer