Fractions - Part 2

  1. What is the common denominator between 1/3 and 3/4?
    12
  2. What is the common denominator between 3/8 and 7/12?
    24 (because both 8 and 12 are factors of 24). 
  3. Add: 1/3 + 3/4 = ?
    =(4/4)(1/3) + (3/4)(3/3)
    =4/12 + 9/12
    =13/12
  4. Add: 3/2 + 5/8 = ?
    = (4/4)(3/2) + 5/8  Here we get a common denominator quickly.
    = 12/8 + 5/8
    = 17/8
  5. Add: 11/12 - 3/8 = ?
    = (2/2)(11/12) - (3/8)(3/3)
    = 22/24 - 9/24
    = 13/24