Annie brought 20 brownies to school. She gave half of them to the school administrator to put in the faculty lounge. Of the remaining brownies, she gave half to her best friend, Carl, and another two to her friend, Simon. How many brownies did she have left? Let's be accurate as possible.
She first gave away half of her 20 brownies, or 20 / 2 = 10 brownies, to the faculty. The remaining brownies number 20 - 10 = 10 brownies. She gave half of these remaining brownies, or 10 / 2 = 5 brownies, to Carl. This reduced her number from 10 down to 10 - 5 = 5 brownies. Finally, she gave away another 2, leaving her with 5 - 2 = 3 brownies.
The answer: 3.