So yesterday my roommate and I went grocery shopping. Now, before I explain, I have to state that I already knew how I've been at conducting mathematical operations, I just hadn't noticed the extent of this inability until this point.
We finished shopping and reached the counter to pay for our things, and subsequently asked the cashier to split the bill who then responded back after processing all our food, "how much is half of that?" My competitive nature urged me to calculate half of an uneven number as quickly as possible. I "figured" out the answer and quickly shouted "$56.30!". Perhaps it was just me, but I sensed a look of doubt in everyone's faces, which made me question the reliability of my answer (the bill was $103.61). Gladly, they aren't aware that I'm an economics and accounting major.
Soon afterwards my roommate corrected me with his trustee calculator (on his phone), which confirmed to all my embarrassing margin of error (I swear I'm not that bad at math but this was the straw that broke the camel's back).
For quite some time now, I've wanted to learn how to compute complex arithmetic in my head to free myself of the common dependance on a calculator. This episode pushed me into action; I just purchased a book on mental arithmetic, and by the end of this year I hope to become a mathematical wiz - to the point of using this ability as a party trick. That's when I'll know that I no longer suck at math.