As usual, let us make a drawing of the distribution:
In general, a z-score says how far from the mean a (data) point is. If we have a data point x, its corresponding z-score can be calculated by
[tex]z_x=\frac{x-\mu}{\sigma}[/tex]
where "mu" represents the mean, and "sigma" represents the standard deviation. Let's calculate the z-scores for 229cm and 77.2cm:
[tex]z_{229}=\frac{229\operatorname{cm}-172.16\operatorname{cm}}{5.95\operatorname{cm}}\approx9.55[/tex][tex]z_{77.2}=\frac{77.2\operatorname{cm}-172.16\operatorname{cm}}{5.95\operatorname{cm}}\approx-15.96[/tex]
Now, note that
[tex]15.96=|z_{77.2}|>|z_{229}|=9.55[/tex]
When this is the case, we say that 77.2cm is more extreme (or is further away from the mean) than 229cm. Namely, the shortest living man had a more extreme height than the tallest one.
Comment: (Be careful!) Note that in the inequality, I consider the absolute value of the z-scores. The sign just says whether x is on the left or on the right of the mean; if z_x is negative, x is on the left, and if z_x is positive, x is on the right of the mean.