Step 1: Write the SHM equation.
For SHM,
\[
x=A\sin\omega t
\]
Given:
\[
A=10\text{ cm}=0.1\text{ m}
\]
and
\[
T=0.6\text{ s}
\]
Angular frequency:
\[
\omega=\frac{2\pi}{T}
\]
\[
\omega=\frac{2\pi}{0.6}
=
\frac{10\pi}{3}
\]
Step 2: Find the time to travel \(5\text{ cm}\).
Starting from equilibrium position:
\[
x=5\text{ cm}=0.05\text{ m}
\]
Using
\[
x=A\sin\omega t,
\]
we get
\[
0.05=0.1\sin\omega t
\]
\[
\sin\omega t=\frac12
\]
Therefore,
\[
\omega t=\frac{\pi}{6}
\]
Thus,
\[
t=\frac{\pi/6}{10\pi/3}
\]
\[
t=\frac{\pi}{6}\cdot \frac{3}{10\pi}
\]
\[
t=\frac{1}{20}\text{ s}
\]
\[
t=0.05\text{ s}
\]
Step 3: Calculate mean velocity.
Mean velocity:
\[
v_{\text{mean}}=\frac{\text{displacement}}{\text{time}}
\]
Displacement from equilibrium to \(5\text{ cm}\):
\[
=0.05\text{ m}
\]
Hence,
\[
v_{\text{mean}}=\frac{0.05}{0.05}
\]
\[
v_{\text{mean}}=1\text{ ms}^{-1}
\]
Step 4: Final conclusion.
Therefore,
\[
\boxed{1\text{ ms}^{-1}}
\]