Question 1206109:  In a large city, 37% of all restaurants accept both master and visa credit cards, and 50% accept master cards and 60% accept visa cards. A tourist visiting the city picks at random a restaurant at which to have lunch. Define the following events: 
 
M
 
M = {the randomly chosen restaurant accepts master credit cards},
 
V
 
V = {the randomly chosen restaurant accepts visa credit cards}.
 
Which of the following shows independence between two events M
 
M and V
 
V? [CHECK ALL THAT APPLY] 
 
A. P(V given M) is equal to P(V)
 
B. The events M and V are not disjoint
 
C. The events M and V are not disjoint
 
D.P(M given V) is equal to P(V)
 
e.P(M and V) is equal to P(M)×P(V)
 
F.P(M given V) is equal to P(M) 
 Found 2 solutions by  ikleyn, math_tutor2020: Answer by ikleyn(52903)      (Show Source): 
You can  put this solution on YOUR website! .
 
 
This current post is a severely worsened formulation of the problem from another post
 
https://www.algebra.com/algebra/homework/Probability-and-statistics/Probability-and-statistics.faq.question.1206108.html
 
 
 
That different formulation was resolved in the referred post.
 
 
This given formulation in the current post is worsened so much that cannot be considered as a mathematical problem.
 
 
 
 
 Answer by math_tutor2020(3817)      (Show Source): 
You can  put this solution on YOUR website!  
It seems strange that answer choices B and C are identical. A typo perhaps?
 
 
M = restaurant accepts MasterCard 
V = restaurant accepts Visa
 
 
Given information 
P(V and M) = 0.37 
P(M) = 0.50 
P(V) = 0.60
 
 
We can then compute the following 
P(V given M) = P(V and M)/P(M) 
P(V given M) = 0.37/0.50 
P(V given M) = 0.74 
Note how this is not the same value as P(V) = 0.60 
Therefore the equation P(V given M) = P(V) is false 
Consequently it means events M and V are not independent. One event affects the other, or vice versa, or the two events are linked somehow.
 
 
Events M and V are not disjoint since P(V and M) = 0.37 is nonzero. 
In other words, it's possible for both events to happen simultaneously. There is overlap between events.
 
 
Side note: An example of disjoint events would be "getting heads" and "getting tails" on the same coin on the same flip.
 
 
P(M given V) = P(M and V)/P(V) 
P(M given V) = 0.37/0.60 
P(M given V) = 0.61667 approximately 
This is not the same as P(M) = 0.50, so the equation P(M given V) = P(M) is false. This is more proof that events M and V are not independent.
 
 
Because those events are not independent, P(M and V) = P(M)*P(V) is false.  
Here is proof of such 
P(M)*P(V) = 0.50*0.60 = 0.30 which doesn't match with P(M and V) = 0.37
 
 
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Summary: 
If M and V were independent, then the following three equations would be true 
P(V given M) = P(V) 
P(M given V) = P(M) 
P(M and V) = P(M)*P(V) 
But we've shown that none of the equations are satisfied, so the events are not independent. 
 
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