My calculator gives all answers in fractions. How can I get it to give me decimal answers?

If I divide a number by another, my Casio fx-82ES scientific calculator only gives me fractions instead of decimal answers. For example, if I divide 1 by 2 it gives me 1/2 instead of 0.5. It's really annoying, and it used to give me normal answers. What do I need to do different for normal decimal answers?