Add 20/30 and 54/21
1st number: 20/30, 2nd number: 2 12/21
20/30 + 54/21 is 68/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
54/21 = 54 × 10/21 × 10 = 540/210 - Add the two like fractions:
140/210 + 540/210 = 140 + 540/210 = 680/210 - 680/210 simplified gives 68/21
- So, 20/30 + 54/21 = 68/21
In mixed form: 35/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/30+54/21 20/60+54/21 20/30+54/42 60/30+54/21 20/90+54/21 20/30+54/63