A stock that sold for 22$ at the beginning of the year was selling for 24$ at the end of the year. If the stock paid a dividend of .50$ per share,what is the simple intrest rate on a investment in this stock?

Question

The simplest answer is that it depends on what the owner paid for the stock.
I think your text wants you to use the average price of the share for the year as the basis, so (24+22)/2 = 23 and .5/23 = .022 or 2.2%
But definitely check to see what the text says to use for the basis.