Question

Which of the following can be used as a variable?

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

Answer 1

The correct option is C a

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.