Question

A speaks truth in 80% cases and B in 60% cases. In what percentage of case are they likely to contradict each other in

starting the same fact :

• A. 44%
• B. 56%
• C. 42%
• D. 48%

Answer 1

Answer: (A)

44%

Answer 2

P(1) = 4/5

P(2) = 3/5

Reqd. prob. = P(1) P( $\overline { \mathrm { B } }$ ) + P( $\overline { \mathrm { A } }$ ) P(2)

= $\frac { 4 } { 5 }$ × $\frac { 3 } { 5 }$

= $\frac { 11 } { 25 }$ or 44%