Calculator help

I tried plugging in 25root2 over 3 ×8root2 onto my calculator and it gave me the answer of 400/3 but when I did ans ÷2 it gave me a math error. I tried it on my old calculator and it gave me the answer of 200/3 but my new calculator gave me a math error so I had to do ans×1/2 for it to work. Any ideas on how I can fix this problem so I can just do ÷2 straight away without getting a math error. BTW the new calculator I have is the fx 991EX classwiz
Thank you!

If you saw my last ignore please I misinterpreted this.
It worked fine when I tried it on my own 991EX.

Oh ok then my calculator just has something wrong with it

Far more likely you've got your calculator in some funny mode than something more significant.