Basic SED doubt

Hi Friends!!

I want to add a / at the end of a number. for example i have CQ65758 /, in this case i want to shift that backspace one space to the left so the my result becomes CQ65758/.
How can i do that with sed.

Thanks
Adi

s%\([0-9]\) /%\1/%

na i gave me tha same output, no change

i got it thanks