It would help to know which system you are using. From the example you gave, you are probably using a version of DnD, but there are many of those!
If you're using 3.5, check out this link:
http://www.d20srd.org/extras/d20encountercalculator/
It is based on all the charts and tables from the DMG that regard how much experience you give per encounter. In your example (assuming the PCs are all ECL 1 and the Kobolds are as given in their base stat block CR 1/4), each PC would get 100 XP.
However, you may be talking about Pathfinder, since they changed it up and assigned an XP value to monsters (much like they had in editions of DnD prior to 3.X). Here's the link for that version of DnD:
http://www.d20pfsrd.com/gamemastering
In your example, you have six players, so the Average Party Level is increased by one. So if everyone is level one (again, assuming that since you're throwing low level kobolds at them), the APL is 2. Kobolds in Pathfinder are actually higher challenges than the one you listed, but I'll take your word that adding up their XP equals 200. In that case, going by the table on the page I linked you to, each player gets 35 XP. However, as I mentioned, kobolds on the Pathfinder SRD give 100 XP apiece, placing the combined XP at the much higher 800 XP and increasing the divided reward to 135 apiece.
If you're in another version of DnD... I can't help you. Which is why it's important to say
which system you're using when asking this sort of question.