Final answer:
The greatest common factor (GCF) of 4r³ and 8 is 8.
Step-by-step explanation:
To find the greatest common factor (GCF) of the expressions 4r³ and 8, we need to factor each expression completely.
The prime factorization of 4r³ is 2 * 2 * 2 * r * r * r.
The prime factorization of 8 is 2 * 2 * 2.
Now, let's compare the common factors in each expression. The common factors are 2 * 2 * 2, which simplifies to 8.
Therefore, the GCF of 4r³ and 8 is 8.