Voted Best Answer
Jan 23, 2014 - 08:10 AM
This exact thing has happened to me a few times. I find that if I completely erase my answer and retype it, exactly as I did the first time, the program accepts it as correct. I don't know if it's a glitch in the program or a failure of the memory in my computer. It's only happened 3 or 4 times through four levels of the program so I tend to think it's my computer. Try retyping to see if it comes up correct.