Answer:
The standard error for her sample is SE = 0.6095
Step-by-step explanation:
By definition, the standard error of the mean is:
Where:
is the standard deviation
is the sample size.
For the information provided in the problem we know that:
Then we introduce these values in the formula of the error to obtain the value.
Answer:
A=a+b
2h=20+8
2·20.4≈285.6
Step-by-step explanation:
Answer:
22 pi
Step-by-step explanation:
Answer:
3.24% of rods will be discarded
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean and standard deviation , the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
What proportion of rods will be discarded
Shorter than 24.85.
pvalue of Z when X = 24.85
has a pvalue of 0.0162
Longer than 25.15
1 subtracted by the pvalue of Z when X = 25.15
has a pvalue of 0.9838
1 - 0.9838 = 0.0162
2*0.0162 = 0.0324
3.24% of rods will be discarded
Answer:-3/9
Step-by-step explanation:
When you adding or subtracting fractions they need to have the same denominator... which in the question they do! :) after you get your denominator the same you add the second numerator from the first one, in this one it’s 3 + (-6). Oh no a negative! But don’t worry when you add a negative it’s just like subtracting a regular number, so you really are just doing 3-6 which is -3 then you just put that over the denominator you had before, and you get -3/9