I have three Pearson correlation coefficients (.8978, .5676 and .7865) for three age groups (i.e. 21 to 30 years, 31 to 40 years and 41 to 50 years) whose behavior I am studying in regard to their shopping habits versus weight gain.

Can I say that .8978 is the strongest relationship between shopping habits and weight gain? 

Based on the difference in the coefficients, can I say that there is a difference in the shopping habits and weight gain of the three age groups?

Finally, can I just add the the three coefficients and divide by three to come up with an average?

All these are 'face value' interpretations. Are they acceptable or do I need to perform some sort of statistical analysis? If it is the latter (heaven forbid), can SPSS do it?