This sort of thing is generally considered "bad" (using a ternary operator to wholly replace an if-statement):
(grade >= 60) ? printf("Passed!\n") : printf("Uh-ohhh...\n");
Generally, you should prefer an if statement to the ternary operator if the operands to the ?: are verbs or complex expressions with side-effects (as they are above: printing).
The second example is a more acceptable use of the ternary operator:
puts(grade >= 60 ? "Passed!\n" : "Uh-ohhh...\n");