The probability that a student has a Visa card (event V) is .63. The probability that a student has a MasterCard (event M) is .11. The probability that a student has both cards is .03. (a) Find the probability that a student has either a Visa card or a MasterCard. (Round your answer to 2 decimal places.) Probability .77 .77 Incorrect (b) In this problem, are V and M independent

Respuesta :

Answer:

a)  The probability that a student has either a Visa card or a MasterCard is 0.71.  

b) V and M are not independent.

Step-by-step explanation:

Given : The probability that a student has a Visa card (event V) is 0.63. The probability that a student has a MasterCard (event M) is 0.11. The probability that a student has both cards is 0.03.

To find :

a) The probability that a student has either a Visa card or a MasterCard ?

b)  In this problem, are V and M independent ?

Solution :

The probability that a student has a visa card(event V) is P(V)= 0.63

The probability that a student has a MasterCard (event M) is P(M)= 0.11

The probability that a student has both cards  is [tex]P(V \cap M)=0.03[/tex]

a) Probability that a student has either a Visa card or a Master Card is given by,

[tex]P(V \cup M) = P(V) + P(M) - P(V\cap M)[/tex]

[tex]P(V \cup M) = 0.63+ 0.11- 0.03[/tex]

[tex]P(V \cup M) =0.74- 0.03[/tex]

[tex]P(V \cup M) =0.71[/tex]

The probability that a student has either a Visa card or a MasterCard is 0.71.

b) Two events, A and B, are independent if [tex]P(A\cap B)=P(A)P(B)[/tex]

For V and M to be independent the condition is satisfied,

[tex]P(V\cap M)=P(V)P(M)[/tex]

Substitute the values,

[tex]0.03=0.63\times 0.11[/tex]

[tex]0.03\neq 0.0693[/tex]

So, V and M are not independent.