Answer:
Step-by-step explanation:
A
According to the exercise we can say that the explanatory variable will be hours / weeks of study.
The response variable is GPA.
B
We definitely found that between the variables there is a weak or fragile relationship, neither negative nor positive nor linear.
C)
1.Observational study, since we observe that the only variables that will influence the results of the study are the observations of the students
2.No. This study is observational and its characteristics are not sufficient to conclude that studying more hours leads to obtaining a higher GPA.
Answer:Given:
P(A)=1/400
P(B|A)=9/10
P(B|~A)=1/10
By the law of complements,
P(~A)=1-P(A)=399/400
By the law of total probability,
P(B)=P(B|A)*P(A)+P(B|A)*P(~A)
=(9/10)*(1/400)+(1/10)*(399/400)
=51/500
Note: get used to working in fraction when doing probability.
(a) Find P(A|B):
By Baye's Theorem,
P(A|B)
=P(B|A)*P(A)/P(B)
=(9/10)*(1/400)/(51/500)
=3/136
(b) Find P(~A|~B)
We know that
P(~A)=1-P(A)=399/400
P(~B)=1-P(B)=133/136
P(A∩B)
=P(B|A)*P(A) [def. of cond. prob.]
=9/10*(1/400)
=9/4000
P(A∪B)
=P(A)+P(B)-P(A∩B)
=1/400+51/500-9/4000
=409/4000
P(~A|~B)
=P(~A∩~B)/P(~B)
=P(~A∪B)/P(~B)
=(1-P(A∪B)/(1-P(B)) [ law of complements ]
=(3591/4000) ÷ (449/500)
=3591/3592
The results can be easily verified using a contingency table for a random sample of 4000 persons (assuming outcomes correspond exactly to probability):
===....B...~B...TOT
..A . 9 . . 1 . . 10
.~A .399 .3591 . 3990
Tot .408 .3592 . 4000
So P(A|B)=9/408=3/136
P(~A|~B)=3591/3592
As before.
Step-by-step explanation: its were the answer is
Answer:
205÷5=41
Step-by-step explanation:
I know its right
Answer:
5%
Step-by-step explanation:
Lets say 10 add a 0 = 100 9.5 add a 0 = 95.0 (move ok decimal place) so there is a 5% error.
