You don't need to solve the math problem. Chances are you can get away with the one good word. If it really bothers you that much just click the reload button (on the captcha box) and you will get a new captcha.
the only word you have to do correctly is the one with all the letters placed slightly differently vertically currently
if its the second word i think you need to put something then a space before it though
anything which looks like it came out of a book is the scanning recognition thing they do, the ones you need to get right are the randomly generated ones