1 / 24

S1 Fractions

fractions, simplifying, multiplying, adding, subtracting

brzezinski
Download Presentation

S1 Fractions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. S1 Fractions Parent Class

  2. Fractions Two fifths is written as: 2 two parts Numerator out of 5 five parts altogether Denominator

  3. Fraction of an amount 2 5 3 6 divide by the denominator and multiply by the numerator of £24 of 18 litres When we work out a fraction of an amount we Examples, = 18 ÷ 3 × 2 = 24 ÷ 6 × 5 = 6 × 2 = 4 × 5 = £20 = 12 litres

  4. Question Time (Question 1)

  5. Simplifying fractions Which of these fractions are expressed in their lowest terms? 14 20 3 15 14 32 16 27 13 21 35 15 A fraction is said to be expressed in its lowest termsif the numerator and the denominator have no common factors. 7 5 2 8 7 5 Fractions which are not shown in their lowest terms can be simplified by cancelling.

  6. Question Time (Question 2)

  7. Mixed and Improper Fractions 15 15 15 is an improper fraction or top heavy. 4 4 4 3 3 4 When the numerator of a fraction is larger than the denominator it is called an improperfraction. We can write improper fractions as mixed numbers. can be visually shown as 15 ÷ 4 = 3 remainder 3 =

  8. Improper fractions to mixed numbers + + + + = 1 1 1 1 8 8 8 5 8 5 = + + + + 8 8 8 8 8 8 37 37 37 = 8 8 8 4 4 4 4 5 5 5 = 8 8 Convert to a mixed number. This number is the remainder. 4 37 ÷ 8 = 4 remainder 5 This is the number of times 8 divides into 37.

  9. Mixed numbers to improper fractions 3 3 1 1 1 = + + + 7 7 7 2 2 2 2 7 7 7 7 7 7 7 = + + + 23 = 7 7 Convert to an improper fraction. … and add this number … To do this in one step, 3 3 … to get the numerator. 2 2 23 = 7 7 Multiply these numbers together …

  10. Question Time (Question 3 & 4)

  11. Multiplying Fractions 3 3 2 4 What is × ? 8 8 5 5 = × 40 3 = 10 To multiply two fractions together, multiply the numerators together and multiply the denominators together: 3 12 10

  12. 12 5 5 4 What is × ? 25 6 5 35 12 × = 6 25 5 2 = Multiplying Fractions Start by writing the calculation with any mixed numbers as improper fractions. To make the calculation easier, cancel any numerators with any denominators. 7 2 14 5 1

  13. Question Time (Question 6)

  14. Adding & Subtracting Fractions 3 + 1 3 1 4 5 5 5 5 When fractions have the same denominator it is quite easy to add them together and to subtract them. For example, + = = We can show this calculation in a diagram: + =

  15. 7 – 3 4 – 8 8 1 7 3 8 2 8 Adding & Subtracting Fractions 1 = = = 2 Fractions should always be cancelled down to their lowest terms. We can show this calculation in a diagram: = –

  16. + + = = = 1 3 1 4 7 9 9 3 9 9 12 1 1 9 Adding & Subtracting Fractions 1 3 Top-heavy or improper fractionsshould be written as mixed numbers.

  17. 3 1 2 5 5 5 7 4 3 Adding & Subtracting Fractions = + Add your whole numbers together and then your fractions.

  18. Question Time (Question 5)

  19. Fractions with different denominators For example, 1 1 What is + ? 2 3 5 2 3 + 2 3 6 6 6 6 Fractions with different denominators are more difficult to add and subtract. We can show this sum using diagrams: + = + = =

  20. 1 3 What is + 3 4 13 9 3 4 1 1 3 12 12 12 12 4 1 1. Write each fraction over the lowest common denominator. ×3 ×4 + ×3 ×4 = + 2) Add the fractions together. = =

  21. 1 3 What is + 3 5 14 3 9 9 5 1 5 3 15 5 15 15 15 15 6 4 2 1) Write each fraction over the lowest common denominator. 4 4 2 2 ×5 ×3 + + ×5 ×3 = + 2) Add the fractions together. 6 = =

  22. 1 2 What is - 7 3 11 14 2 14 3 1 3 21 21 21 21 3 7 21 3 2 5 1) Write each fraction over the lowest common denominator. 2 2 5 5 ×3 ×7 - - ×3 ×7 - = 2) Subtract the fractions together. 3 = =

  23. A problem with subtractions 3 1 What about - 4 5 2 9

  24. Question Time (Question 7)

More Related