MHT CET2008MathematicsSets and Relations
The chances to fail in Physics are 20 % and the chances to fail in Mathematics are 10 % . What are the chances to fail in at least one subject?
Options
- A28 %
- B38 %
- C72 %
- D82 %
Correct answer
A. 28 %
Step-by-step solution
Let P(A)= 20 100 = 1 5 , P(B)= 10 100 = 1 10 Since, event are independent and we have to find aligned P(A& B)=P(A)+P(B)-P(A) P(B) &= 1 5 + 1 10 - 1 5 1 10 &= 3 10 - 1 50 = 14 50 = 14 50 100=28 % aligned