Download
adding fraction with different denominator n.
Skip this Video
Loading SlideShow in 5 Seconds..
Adding Fraction With Different Denominator PowerPoint Presentation
Download Presentation
Adding Fraction With Different Denominator

Adding Fraction With Different Denominator

155 Vues Download Presentation
Télécharger la présentation

Adding Fraction With Different Denominator

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Adding Fraction With Different Denominator

  2. Definition • Common Denominator – When the fractions in an addition problem do not have the same denominators, rewrite the problem so that each fraction has the same denominator. • Lowest Common Denominator – A common denominator is a number that can be divided evenly by all the denominators in a problem. The smallest number that can be divided evenly by all the denominators in a problem. • Sometimes the largest denominator is a problem is the lowest common denominator.

  3. Finding a Common Denominator Here are two ways of finding a common denominator when the largest denominator in addition problem doesn’t work. • Multiply the denominators together. • Go through the multiplication table of the largest denominator.

  4. 2/5 + 3/4 = Multiply the denominators. 5 X 4 = 20. 20 is the lowest common denominator (LCD). Raise each fraction to 20ths . Add the new fractions. Change the answer to a mixed number. 2/5 = 8/20 + 3/4 =15/20 23/20 = 1 3/20 Example 1

  5. 2/3 + 5/6 + 3/4 = Go through the multiplication table of the 6’. 6 x 1 = 6, which cannot be divided by 4. 6 x 2 = 12, which can be divided by 3 and 4. Raise each fraction to 12ths. Add the new fractions. Change the answer to a mixed number and reduce. 2/3 = 8/12 5/6 =10/12 +3/4 = 9/12 27/12 = 2 3/12 = 2 1/4 Example2

  6. 3/5 + 2/3 = 3/7 + 1/3 = 1/4 + 3/5 + 7/10= 2/3 + 4/9 + 5/6 = 4 3/5 + 6 ¾ = 6 5/12 + 7 3/8 = Practice