Answer:
42.1% of variation in the response is explained by the regression line
Step-by-step explanation:
Correlation coefficient is a measure which tells us that how strongly are two variables under study are linearly related to each other i.e correlation coefficient gives the strength of linear association between the variables.
If the magnitude of correlation coefficient is closer to 1, it indicates a strong linear relationship. If the magnitude of correlation coefficient is closer to 0, it indicates a weak linear relationship.
There is another variable known as "Coefficient of Determination", which is equal to square of Correlation Coefficient. Coefficient of Determination tells us that what percentage of variation in the response of the study can be explained by the regression line.
This means, for this question we need to calculate the Coefficient of Determination.
Correlation coefficient = r = 0.649
Coefficient of Determination = R = r² = (0.649)²= 0.421 = 42.1 %
This means that 42.1% of variation in the response is explained by the regression line.
Answer:
hahaha me
Step-by-step explanation:
...actually how old are you though lol
Answer:
Cluster sample
Step-by-step explanation:
This is an example of a cluster sample. In a cluster sample, the examiner divides the population into groups (each one of these groups is called a cluster) and once the examiner has these clusters, takes one of them and recollects the data from ALL the members of that cluster. In this case, the teacher divided the class in 3 different groups and then selects one of these groups and asks the average amount of time per week he/she spent studying.
Given:
μ = 2 min, population mean
σ = 0.5 min, population standard deviation
We want to find P(x>3).
Calculate the z-score
z= (x-μ)/σ = (3-2)/0.5 = 2
From standard tables, obtain
P(x ≤ 3) = P(z ≤ 2) = 0.9772
Therefore
P(x > 3) = P(z > 2) = 1 - 0.9772 = 0.0228
Answer: 0.02275