Question

greatest common factor - item 34686
what is the greatest common factor of 15 and 30?
the gcf of 15 and 30 is

Explanation:

Step1: Find factors of 15

The factors of 15 are the numbers that divide 15 without leaving a remainder. So, $1 \times 15 = 15$, $3 \times 5 = 15$. Thus, the factors of 15 are $1, 3, 5, 15$.

Step2: Find factors of 30

The factors of 30 are found by identifying numbers that multiply to 30. $1 \times 30 = 30$, $2 \times 15 = 30$, $3 \times 10 = 30$, $5 \times 6 = 30$. So, the factors of 30 are $1, 2, 3, 5, 6, 10, 15, 30$.

Step3: Identify common factors

The common factors of 15 and 30 are the numbers that appear in both lists of factors. From the factors of 15 ($1, 3, 5, 15$) and factors of 30 ($1, 2, 3, 5, 6, 10, 15, 30$), the common factors are $1, 3, 5, 15$.

Step4: Determine the greatest common factor

Among the common factors $1, 3, 5, 15$, the greatest one is 15.

Answer:

15