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8. Prime numbers

A whole number is a prime if it is larger than $$1$$ and the only whole numbers that divide it are $$1$$ and itself.

Example Which of the numbers from $$1$$ to $$10$$ are prime?

Solution $$\downarrow$$
$$1$$ is not prime since it is not larger than $$1$$
$$2$$ is prime since only $$1$$ and $$2$$ divide $$2$$
$$3$$ is prime since only $$1$$ and $$3$$ divide $$3$$
$$4$$ is not prime since $$2$$ divides $$4$$
$$5$$ is prime since only $$1$$ and $$5$$ divide $$5$$
$$6$$ is not prime since $$2$$ divides $$6$$
$$7$$ is prime since only $$1$$ and $$7$$ divide $$7$$
$$8$$ is not prime since $$2$$ divides $$8$$
$$9$$ is not prime since $$3$$ divides $$9$$
$$10$$ is not prime since $$2$$ divides $$10$$

Is this a prime number?