Answer
$\frac{1}{4}$
Work Step by Step
Let's assume that reciprocal of 4 is '$ x$'.
By definition, product of a number and its reciprocal is always 1. Therefore-
$ 4 \times x$ = 1
or $ x$ = $\frac{1}{4}$
i.e. reciprocal of 4 is $\frac{1}{4}$