The National Academies of Sciences, Engineering, and Medicine are private, nonprofit institutions that provide expert advice on some of the most pressing challenges facing the nation and world. Our ...

Teaches pilots to solve aviation math problems mentally, without calculators. Covers essential areas like fuel planning, temperature conversions, and time-speed-distance calculations. Offers practical ...

Time to test your brain! Are you a puzzle person? Most of these hard math problems aren’t straightforward arithmetic. They challenge you to look at problems a different way, testing your logic and ...