What’s girl math? It’s something that only makes sense if you’re a woman. For example: “calories don’t count when you’re on your period”, or “not paying the $15 for shipping instead spending another $30 to get the free shipping“, or “packing a minimum of 14 pairs of underwear for a 7 day trip”. If you’re a man, it’s important to understand girl math so you can understand women a little better. If you’re a woman, this post will be very relatable. Scroll down to see the funniest examples!