Answers

Solutions by everydaycalculation.com

Answers.everydaycalculation.com » Add fractions

Add 21/18 and 18/21

1st number: 1 3/18, 2nd number: 18/21

21/18 + 18/21 is 85/42.

Steps for adding fractions

  1. Find the least common denominator or LCM of the two denominators:
    LCM of 18 and 21 is 126

    Next, find the equivalent fraction of both fractional numbers with denominator 126
  2. For the 1st fraction, since 18 × 7 = 126,
    21/18 = 21 × 7/18 × 7 = 147/126
  3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
    18/21 = 18 × 6/21 × 6 = 108/126
  4. Add the two like fractions:
    147/126 + 108/126 = 147 + 108/126 = 255/126
  5. 255/126 simplified gives 85/42
  6. So, 21/18 + 18/21 = 85/42
    In mixed form: 21/42

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad

Related:

© everydaycalculation.com