Answer: The variables have a weak positive correlation
Since r > 0, the correlation is positive. It's a weak correlation because r is closer to 0 than it is to 1.
Answer: D. 40
Step-by-step explanation:
Given: Number of students liked vanilla or chocolate ice cream =
Number of students liked chocolate =
Number of students liked vanilla=
Now, Number of students liked vanilla and chocolate ice cream is given by :-

Number of students liked vanilla and chocolate ice cream= 40
The formulas for conditional probability are:


.
Since

and

, you have the equation

.
Therefore,

.
Answer: The correct choice is D.
By the way the question is worded, I would say you undo addition by subtraction. I hope this helped!
Answer:
The value of X is 
Step-by-step explanation:
Given : 
To find : The value of X ?
Solution :

Converting ratios into fraction,


Cross multiply,



Therefore, The value of X is 