As an example, let’s have a look at the mean age by smoking status categories.

1. Analyze > Descriptive Statistics > Explore …
2. Place your categorical variable (smokestat) in the “Factor List:” box, and your continuous variable (age) in the “Dependent List:” box.
3. Click Paste, then run selection from your syntax file.
4. Your output should look something like this:

This tells us, for example, that the mean age of those who have never smoked, is 19.8 years (SD=3.8), and that the mean age for current smokers is 21.1 years (SD=9.3).  You can see that we also get a lot of other descriptive information about age according to smoking status.