Number System
The Number System is the core foundation of mathematics and quantitative aptitude. It is a mathematical way of representing numbers using a set of symbols or digits. In the simplest terms, it explains how we count, measure, and compare quantities. We start with Natural Numbers, which are basic counting numbers starting from 1. When we include zero, they are called Whole Numbers. Integers expand this to include negative values, like -1 and -2.
Concepts (2)
Rules for combining numbers are fixed. Adding two even numbers gives an even number. Adding two odd numbers also gives an even number. One even and one odd added together always result in an odd number.
Rules for combining numbers are fixed. Adding two even numbers gives an even number. Adding two odd numbers also gives an even number. One even and one odd added together always result in an odd number. In multiplication, if even one number is even, the final result is even. Example: 3 (odd) + 5 (odd) = 8 (even). 3 (odd) x 4 (even) = 12 (even).
The last digit of a number raised to a power repeats in a cycle. For example, powers of 2 end in 2, 4, 8, 6, and then repeat. The cycle length is usually 4. To find the unit digit of 2 raised to 10, divide 10 by 4. The remainder is 2.
The last digit of a number raised to a power repeats in a cycle. For example, powers of 2 end in 2, 4, 8, 6, and then repeat. The cycle length is usually 4. To find the unit digit of 2 raised to 10, divide 10 by 4. The remainder is 2. So, the unit digit is the same as 2 raised to 2, which is 4.
Ready to practice? Start an interactive lesson.
Start Lesson: Even and Odd Properties