Numerals and Fractions UNIT 1 Numerals and Fractions

Key Terms Denominator Numerator Lowest common denominator (LCD) Lowest terms Mixed number

Arabic vs. Roman Arabic numerals Roman numerals Figures 0–9 Used in everyday calculations Roman numerals Use letters to represent numbers Sometimes used on medication orders (continues)

Arabic vs. Roman 1 5 10 50 100 500 1,000 I V X L C D M

Roman Numeral Rules When two or more numerals of same value are together, add values (CCC = 100 + 100 + 100 = 300) When a larger numeral precedes a smaller numeral, add the values (XV = 10 + 5 = 15) (continues)

Roman Numeral Rules When a smaller numeral precedes a larger numeral, subtract the values (XC = 100 – 10 = 90) When a numeral is between two numerals of larger value, subtract the lesser value from the following numeral (CIX = 100 + 10 – 1 = 109)

Types of Fractions Simple fractions Compound fractions One numerator and one denominator Compound fractions Requires mathematical process in either numerator or denominator (continues)

Types of Fractions Complex fractions Proper fractions Have simple fractions in either numerator, denominator, or both Proper fractions Numerator is smaller than denominator (continues)

Types of Fractions Improper fractions Mixed number Numerator is larger than denominator Mixed number Whole number and a fraction Equivalent fractions Two or more fractions that have the same value

Relative Values Determine which fraction is largest Make each fraction a whole number Fraction that takes fewest parts to make whole number is largest When fractions share same denominator, fraction with largest numerator is largest fraction

Adding Fractions Denominators must be same If denominators are different, must find LCD When adding mixed numbers, may change to improper fraction then reduce If numerator is larger than denominator, divide numerator by denominator

Subtracting Fractions Denominators must be same If denominators are different, must find LCD When subtracting mixed numbers, may change to improper fraction then reduce Subtract numerators, and place answer over denominator

Cancellation Used when dividing or multiplying fractions Allows user to work with smaller numbers (continues)

Cancellation Steps Divide numerators or denominators by largest number in each Continue with math process of problem

Multiplication Whole numbers Mixed numbers Change to fraction by placing whole number over 1 Proceed as you would with other fractions Mixed numbers Change mixed number to improper fraction

Division Whole numbers Change to fraction by placing whole number over 1 Invert the divisor Multiply as you would with any other fraction (continues)

Division Mixed numbers Change to improper fraction Invert the divisor Multiply as you would with any other fraction