I think it is B)Observational studies involve the random selection of subjects.
To find the mean of a dot plot, add up all of the data and divide by how many numbers there are.
In this case, the data added up is 4 + (5 x 4) + (6 x 3) + (7 x 2) + 10
4 + (5 x 4) + (6 x 3) + (7 x 2) + 10 = 66
With this information, we can now find the mean.
66/11=6
Therefore, the mean is 6. Hope this helps! Feel free to ask any questions.
Answer:
Step-by-step explanation:
3(5b-1)=5
Get rid of the brackets
15b-3=5
add 3 to both sides of the equation
15b=8
divide both sides of the equation by 15
b=0.53
4(3y-1)=20
12y-4=20
12y=24
y=0.5