Question

A candidate has to attend Maths and Physics exams. The probability that he passes any exam is $\frac { 1 } { 4 }$ . Then the

probability that he passes atleast one exam is

• A. 9/16
• B. 7/16
• C. 5/16
• D. 11/16

Answer 1

Answer: (B)

7/16

Answer 2

Let A and B the events of passing Maths and physics

respectively.

P(A ∪B) = P(1) + P(2) – P(A∩B)

$\frac { 1 } { 4 } + \frac { 1 } { 4 } - \frac { 1 } { 16 } = \frac { 7 } { 16 }$ .

P(A∪B) = 1 - $\mathrm { P } ( \overline { \mathrm { A } } \cap \overline { \mathrm { B } } )$

= 1 - .