Conjecture is a statement that is believed to be true but not yet proved.
The statement "Sum of the measures of the interior angles in any triangle is 180° " is a conjecture.
Here is another such conjecture: "If two parallel lines are cut by a transversal, the corresponding angles are congruent."
Correct Answer: B
Step 1: A conjecture is a statement that is believed to be true but not yet proved or disproved.
Step 2: Sam's proposition is not a conjecture, because for n = 8, 3n + 1 gives 25, which is not a prime number.