Statistics Help
Question: Roll two dice: first red and second green and observe the number facing up. A and B are defined as A: greater than or equal to 5, B: bothh are even numbers.
Find - p(A∪B)
p(A∩B) Edit
Answer: In a simultaneous throw of two dice, n(S)=6*6=36
Now, A=event of getting greater than or equal to 5 =(1,4)(1,5)(1,6)(2,3)(2,4)(2,5)(2,6)(3,2)(3,3)(3,4)(3,5)(3,6)(4,1)(4,2)(4,3)(4,4)(4,5)(4,6)(5,1)(5,2)(5,3)(5,4)(5,5)(5,6)(6,1)(6,2)(6,3)(6,4)(6,5)(6,6)
B=event of both are even number =(2,2)(2,4)(2,6)(4,2)(4,4)(4,6)(6,2)(6,4)(6,6)
So,(A∩B)=(2,4)(2,6)(4,2)(4,4)(4,6)(6,2)(6,4)(6,6)
So,P(A∩B)= 8/36=4/9 (Ans.)
Now, P(A)=30/36 ; P(B)=9/36
So, p(A∪B)=P(A)+P(B)-P(A∩B)=30/36+9/36-8/36=31/36(Ans.) Edit
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