Question

A speaks truth in 75% of the cases, while B in 90% of the cases. In what percent of cases are they likely to contradict each other in stating the same fact ? Do you think that statement of B is always true ?

Answer 1

Let A and B denote A speaks the truth' and  'B speaks the truth' respectively.

Hence, they are likely to contradict each other in 30% of the cases in stating the same fact. Though B speaks truth in 90% of the cases but he also lies in 10% of the cases. So, his statement is not always true.