JEE Main2014MathematicsProbabilityActual
If A and B are two events such that P A ∪ B = P A ∩ B , then the incorrect statement amongst the following statements is :
Options
- AP A + P B = 1
- BP A ∩ B ' = 0
- CA   &   B are equally likely
- DP A ' ∩ B = 0
Correct answer
A. P A + P B = 1
Step-by-step solution
P A ∪ B = P A ∩ B Using the addition theorem of probability, P A ∪ B = P A + P B - P A ∩ B ⇒ P A = P B P A ∩ B ' = 0 P A ' ∩ B = 0 Here, A and B are equally likely. But we can't say that P A = P B = 1 2 Therefore, P A + P B ≠ 1