lets say i wanted to invest in some friends small business of selling t shirts and hats, they have a few people Investing with them. the first quarter goes by and they see some profits how are these divided up?

It usually depends on how much you invest. For example, say two of your friend put in $500 each and now you come along and put in, say, $200. In that case, you should get ($200 / $1,200) of the profits, or about 17%.

If you also put in $500, then you are all equal parents and you should get 33% of the profits.