Question
I have 4 african violets and three of the four have brown spots on the tips of the leaves. looks like they are drying out and dying but I am not sure why. I have not have a problem berore with this.  

Answer
I wonder if ALL the leaf tips are brown and dry?  This would definitely indicate a problem, most likely a need for more water, or perhaps with the weather warming up a bit it could be that your violets have gotten stronger sunlight than usual. This is something I have to be watchful for in my violets.  They sit in a windowsill, and when the sunlight becomes stronger in spring/summer I usually have to move them back, even take them off the windowsill and place them on a table.  Something else you might try is raising the humidity, either by misting the plants several times a day, or by using the 'humidity tray' method, in which you place your plant or plants on a tray (only the depth of a plate) filled with small pebbles.  The pebbles are kept in water, but be careful that the water is not deep enough for the violets to start leaching water through the bottom.  This would lead to over-watering and root rot. However, if done correctly the humidity tray is an ideal method of raising humidity, and many florists use it.  Whatever the cause of this browning of the leaves you want to address it before you start losing leaves.  Please send a followup if I can help you further.