1. Numerals and Fractions
UNIT 1
Numerals and Fractions

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

3. 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
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4. Arabic vs. Roman 1 5 10 50
100
500
1,000 I V X L C D M

5. Roman Numeral Rules
When two or more numerals of same value are together, add values
(CCC = = 300)
When a larger numeral precedes a smaller numeral, add the values
(XV = = 15)
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6. 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 = – 1 = 109)

7. Types of Fractions Simple fractions Compound fractions
One numerator and one denominator
Compound fractions
Requires mathematical process in either numerator or denominator
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8. Types of Fractions Complex fractions Proper fractions
Have simple fractions in either numerator, denominator, or both
Proper fractions
Numerator is smaller than denominator
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9. 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

10. 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

11. 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

12. 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

13. Cancellation Used when dividing or multiplying fractions
Allows user to work with smaller numbers
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14. Cancellation
Steps
Divide numerators or denominators by largest number in each
Continue with math process of problem

15. 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

16. Division Whole numbers
Change to fraction by placing whole number over 1
Invert the divisor
Multiply as you would with any other fraction
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17. Division Mixed numbers Change to improper fraction Invert the divisor
Multiply as you would with any other fraction