Which numbers are factors of $20$ ? Select all that apply. $\newline$ \begin{tabular}{|l|l|l|l|l|l|} $\newline$ \hline $17$ & $5$ & $9$ & $4$ \\ $\newline$ \hline $\newline$ \end{tabular}

Full solution

Q. Which numbers are factors of

20

? Select all that apply.

\newline

\begin{tabular}{|l|l|l|l|l|l|}

\newline

\hline

17

5

9

4

\newline

\hline

\newline

\end{tabular}

Definition of Factor: Understand what a factor is. $\newline$ A factor of a number is an integer that can be multiplied by another integer to produce that number. To find the factors of $20$ , we need to find all integers that can be multiplied together to give the product of $20$ .
Test $17$ as Factor: Test the first number, $17$ , to see if it is a factor of $20$ . To test if $17$ is a factor of $20$ , we divide $20$ by $17$ and see if the result is an integer without any remainder. $20 \div 17 = 1$ with a remainder of $3$ . Since there is a remainder, $17$ is not a factor of $20$ .
Test $5$ as Factor: Test the second number, $5$ , to see if it is a factor of $20$ . To test if $5$ is a factor of $20$ , we divide $20$ by $5$ and see if the result is an integer without any remainder. $20 \div 5 = 4$ with no remainder. Since there is no remainder, $5$ is a factor of $20$ .
Test $9$ as Factor: Test the third number, $9$ , to see if it is a factor of $20$ . To test if $9$ is a factor of $20$ , we divide $20$ by $9$ and see if the result is an integer without any remainder. $20 \div 9 = 2$ with a remainder of $2$ . Since there is a remainder, $9$ is not a factor of $20$ .
Test $4$ as Factor: Test the fourth number, $4$ , to see if it is a factor of $20$ . To test if $4$ is a factor of $20$ , we divide $20$ by $4$ and see if the result is an integer without any remainder. $20 \div 4 = 5$ with no remainder. Since there is no remainder, $4$ is a factor of $20$ .