GATE | GATE-CS-2006 | Question 26
Which one of the first order predicate calculus statements given below correctly express the following
Tigers and lions attack if they are hungry or threatened.
Explanation: The statement “Tigers and lions attack if they are hungry or threatened” means that if an animal is either tiger or lion, then if it is hungry or threatened, it will attack. So option (D) is correct.
Don’t get confused by “and” between tigers and lions in the statement. This “and” doesn’t mean that we will write “tiger(x) ∧ lion(x) “, because that would have meant that an animal is both tiger and lion, which is not what we want.