Fractions (addition, subtraction, multiplication and (1)
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This document discusses operations involving fractions such as addition, subtraction, multiplication, and division of fractions. It defines key fraction terms like numerator, denominator, mixed numbers, proper and improper fractions. It provides steps and examples for performing each operation on fractions. The steps for addition and subtraction involve finding a common denominator and then adding or subtracting the numerators. Multiplication involves multiplying the numerators and denominators. Division is performed by changing the second fraction to its reciprocal and then multiplying.
Fractions (addition, subtraction, multiplication and (1)
- 1. FRACTIONS (ADDITION, SUBTRACTION, MULTIPLICATION AND DIVISION OF FRACTIONS) PRESENTED BY: M.P MAPENA S.S.E MNGOMEZULU L.P KGASWANE
- 2. ADDITION AND SUBTRACTION OF FRACTIONS • Fraction is any number or variable that can be written in the form of a/b or b/a. • Consider 3/4 , we say the top number is the numerator and the bottom number is the denominator, so I can conclude by saying the numerator and the denominator makes up the fraction.
- 3. MIXED NUMBERS, PROPER AND IMPROPER FRACTIONS • Mixed number or fraction is when 4/3 can be written in 1 1 3 . • Improper fraction is when the numerator is bigger then the denominator. 4 3 • Proper fraction that is when the numerator is smaller than the denominator. • In maths class we always avoid using mixed number and so we use improper fractions. Why? Because for us to
- 4. ADD AND SUBTRACT FRACTIONS • When adding and subtracting fractions you have to consider the following steps: 1) First find the common denominator 2) Add (or subtract) numerators only 3) Reduce the fraction ( look for the number that will divide the numerator and denominator evenly) 4) Always express your answer in lowest terms.
- 5. EXAMPLES • 8 5 − 3 12 Multiply the denominators and get 60 = 96 60 − 15 60 add/subtract the numerators only = 81 60 reduce the fraction into simple terms = 27 20 Now try this one • 7 4 + 12 5
- 6. MULTIPLICATION OF FRACTIONS • When multiplying fraction you simply multiply the numerator with the numerator and the denominator with the denominator. • When given the mixed number/fraction, you have to first change the mixed fraction into the improper fraction then simply before multiplying. • When ever given the fraction that looks like this 8 9 ∗ 3 4 , Use the rule of maths that says, ‘ when everything is multiplying or dividing we can reduce or cancel something from the numerator and something from the denominator as long as we divide the numbers by the same thing.
- 8. DIVISION OF FRACTIONS •Proper way to divide fractions is to change it into the multiplication form. •How? Write the first fraction without changing it, then change the next fraction into its reciprocal. •Example: 2 5 ÷ 9 4 = 2 5 ∗ 4 9 = 8 45
- 9. EXTRA PROBLEM • Try FOLLOWING 1) 5 8 ÷ 2 10 ÷ 9 2 2) −6 2 5 × 3 ÷ 2 3 4
- 10. RECAP! • Fractions have a numerator and the denominator • Improper fractions are more useful to us the mixed fraction/number. • When adding or subtracting fractions: 1) Find the common denominator. 2) Add (or subtract) numerators only. 3) reduce. • When multiplying use the rule of maths • When dividing the fractions do not forget to change the second fraction to its reciprocal before multiplying.