I’m starting a new job in finance next month, and while I’m obviously going to use Excel for the heavy lifting, I really want to be able to do quick, high-level calculations in my head during meetings without fumbling around with my phone. I’ve always been super slow at multiplication and division. Are there any structured systems or daily exercises I can practice over the next few weeks to boost my mental math speed?

The standard ways they teach math in school take way too long to calculate when you're put on the spot in front of clients.

If you want to get ridiculously fast at mental arithmetic without resorting to scratch paper, you need to abandon the traditional school methods entirely. Look up the Trachtenberg system—it was literally designed by an engineer in a concentration camp to keep his mind sharp, and it relies on rapid, simplified rules for shortcutting complex multiplication. There is an excellent breakdown of how to use it here at https://memoryos.com/article/the-trachtenberg-method-unlocking-the-power-of-mental-math. Once you learn the specific keys for multiplying numbers without writing down intermediate steps, you’ll be able to calculate large figures in your head faster than someone can even type them into a phone. It takes a bit of practice to memorize the rules, but it’s an absolute game-changer for business meetings.