This subject covers the foundational concepts of number and quantity, focusing on real numbers, complex numbers, and their applications in various mathematical contexts.
Number sense means understanding how numbers work and relate to each other. Practice estimating, comparing numbers, and recognizing patterns. Use mental math tricks to check your work and look for shortcuts to solve problems more efficiently.
Estimating the answer before using a calculator.
Recognizing that \(99 \times 101\) is just \(100^2 - 1\).