Add 72/27 and 20/21
1st number: 2 18/27, 2nd number: 20/21
72/27 + 20/21 is 76/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 21 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 27 × 7 = 189,
72/27 = 72 × 7/27 × 7 = 504/189 - Likewise, for the 2nd fraction, since 21 × 9 = 189,
20/21 = 20 × 9/21 × 9 = 180/189 - Add the two like fractions:
504/189 + 180/189 = 504 + 180/189 = 684/189 - 684/189 simplified gives 76/21
- So, 72/27 + 20/21 = 76/21
In mixed form: 313/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/27+40/21 72/54+20/21 72/27+20/42 72/27+60/21 72/81+20/21 72/27+20/63