It approaches a normal distribution.
Because as the sample size increases the Student's t-distribution approaches the standard normal.
Because t-score isn't as accurate as z-score, you should use 40 as a safety sample size, rather than 30 as you would for a z-score.
z=(x-mean)/(standard deviation of population distribution/square root of sample size) T-score is for when you don't have pop. standard deviation and must use sample s.d. as a substitute. t=(x-mean)/(standard deviation of sampling distribution/square root of sample size)
When you don't have the population standard deviation, but do have the sample standard deviation. The Z score will be better to do as long as it is possible to do it.
It approaches a normal distribution.
Because as the sample size increases the Student's t-distribution approaches the standard normal.
Because t-score isn't as accurate as z-score, you should use 40 as a safety sample size, rather than 30 as you would for a z-score.
T score is usually used when the sample size is below 30 and/or when the population standard deviation is unknown.
z=(x-mean)/(standard deviation of population distribution/square root of sample size) T-score is for when you don't have pop. standard deviation and must use sample s.d. as a substitute. t=(x-mean)/(standard deviation of sampling distribution/square root of sample size)
There is not enough information in the question to determine if the t-distribution is the appropriate model to use. If it is, then, with, a sample size of 95 the z-score for the Gaussian distribution is a suitable approximation. The probability is 0.199, approx.
If the sample size is less then 30 use the T table, if greater then 30 use the Z table.
T-score is used when you don't have the population standard deviation and must use the sample standard deviation as a substitute.
a "T" or a "Z" score. A "T" Score if comparing a sample. A "Z" Score when comparing a population. Remember, a population includes all observation, and a sample includes only a random selection of the population.
When you don't have the population standard deviation, but do have the sample standard deviation. The Z score will be better to do as long as it is possible to do it.
There are 24 df.
Yes, but it converges to the Gaussian (Normal) dirstribution for large sample sizes.