9 out of 12 cheevo's, but only 100G??

[adbailey18]

I've only recently picked this up, I finished my first playthrough last night going for the 100% items. When I completed the game I checked my achievements and it says I've unlocked 9 of 12 which should equal 170G yet on xbox live it only says 100G????

Anybody got any ideas or happened to them?

EDIT: Nevermind, today I've loaded the game and checked the achievement tracker in game which shows 170g, then when I used the mini guide it had updated my gamercard!!