Answer:
And if we use the values obtained we got:
For this case this value means that the expected score is about 7.48
Step-by-step explanation:
For this case we assume the following probability distribution:
X 5 6 7 8 9 10
P(X) 0.05 0.15 0.33 0.28 0.12 0.07
First we need to find the expected value (first moment) and the second moment in order to find the variance and then the standard deviation.
In order to calculate the expected value we can use the following formula:
And if we use the values obtained we got:
For this case this value means that the expected score is about 7.48
In order to find the standard deviation we need to find first the second moment, given by :
And using the formula we got:
Then we can find the variance with the following formula:
And then the standard deviation would be given by:
Answer:
A 21 /169
B independent
Step-by-step explanation:
The total number of candies is 7+3+3 = 13
P( 1st red) = red/total = 7/13
Since the candy is put back there are still 13 candies in the dish
P(2nd green) = green/total = 3/13
P( red, then green) = P( 1st red) * P(2nd green)
= 7/13* 3/13 = 21/169
The events are independent since the candies are put back
Answer:
Stratified Sampling
Step-by-step explanation:
Stratified sampling involves dividing the population into subpopulations that may differ in important ways. It allows you draw more precise conclusions by ensuring that every subgroup is properly represented in the sample.
To use this sampling method, you divide the population into subgroups (called strata) based on the relevant characteristic (e.g. gender, age range, income bracket, job role).
Based on the overall proportions of the population, you calculate how many people should be sampled from each subgroup. Then you use random or systematic sampling to select a sample from each subgroup.
I hope this helped!
There are many possible answers.
10:12
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30:36