# Number Theory

### Roman Numerals

Roman Numerals What are Roman Numerals? Roman Numerals are a number system that originated in the ancient Rome that are written by combinations of letters from Latin alphabet. In this system the number we know today are written with letters. Roman numerals use seven letters: I,V, X, L, C, D and M that represents the number 1, […]

### Operations with positive and negative numbers

Operations with positive and negative numbers What are positive and negative numbers?Positive numbers are numbers that are greater then zero.Negative numbers are numbers that are less then zero. Visualizing positive and negative numbers on a number line Positive numbers are written without a sign or with a “+” in front of them. Meanwhile negative numbers […]

### HCF and LCM

HCF and LCM  How to find HCF and LCM? One method to find both HCF and LCM by using Prime factorization. Finding HCF using prime factorization Step 1: Find the prime factors of each given number. Step 2: Identify all the common prime factors of the given numbers. Step 3: Multiply the common factors.The product of these common […]

### Prime and composite numbers 