Question

Which of the following can be used as a variable?

• A. $5$
• B. $a$
• C. $\frac{13}{5}$
• D. $\pi$

Answer 1

The correct option is B

$a$

A variable is a symbol representing a quantity whose value is unknown. Any symbol that doesn't have a fixed value can be used as a variable.

$5$ is an integer, which has a fixed value. It cannot be used as a variable.
$a$ can be used as a variable.
$\frac{13}{5}$ also has a fixed value, which cannot be used as a variable.
$\pi$ is a constant that has a fixed value close to the value of $\frac{22}{7}$. Hence, it cannot be used as a variable.