Experience Buff not adding up.

Experience Buff not adding up.
I am crafting at our house in the Mist. I am level 40. The FC has the Helping Hand II buff which should give me an extra 10% XP. I also am using crafting food that should give me an extra 3% experience.

So:
10% Helping Hand
3% Food Bonus

I have only been getting 12% bonus XP since I started leveling. I am level 40 now. By the time i get to 50 I will have missed out on 7 million XP from that missing 1%. Thats alot of gil/time wasted.

Does anyone have any idea why this is happening?!

I think the bonus xp is rounded down. Then the displayed percentage is rounded down from that.
For example: Something normally gives 50 xp. 13% of 50 is 6,5. That gets rounded down to 6. 6 is 12% of 50. Because of that, it will display 12% bonus.