Welcome to Westonci.ca, your ultimate destination for finding answers to a wide range of questions from experts. Get detailed answers to your questions from a community of experts dedicated to providing accurate information. Join our platform to connect with experts ready to provide precise answers to your questions in different areas.

Cynthia made the conjecture that the sum of any prime number and any composite number is a composite number.

Which equation is a counterexample to her conjecture?

A.
11 + 2 = 13

B.
5 + 8 = 13

C.
13 + 2 = 15

D.
11 + 9 = 20


Sagot :

Well,

We will need an equation in the form of:
(prime no.) + (composite no.) = (prime no.)

Options C and D immediately are rejected because the result is a composite number.

Option A looks like it could be a counterexample, but 2 is a prime number.

That leaves option B, which is the correct option.