  This paper proposes a quantum circuit for computing the mean value from a
given set of numbers or function evaluations. Suppose a Quantum Random Access
Memory is given as a black-box function, which allows us to store and read the
values of a set as quantum states. The proposed quantum algorithm estimate the
mean value of the function by using superposition, interference, and
entanglement phenomena, in $\mathcal{O}(\log{N})$ complexity or in
$\mathcal{O}(1)$ query of the black-box.
