90 math problems designed to challenge you and help you hone your math skills. Each problem is designed to test your limits, and explanations are given with every problem, as well as tips for tackling arithmetical obstacles to make them simpler than they may seem. Also provided are formula sheets including all properties and formula that may be needed for any of the problems. Topics range from simple fractions through basic calculus. Real-world situations are presented in many of the problems to help demonstrate how math can be used outside of the school room.