Add 5/8 and 81/21
1st number: 5/8, 2nd number: 3 18/21
5/8 + 81/21 is 251/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
5/8 = 5 × 21/8 × 21 = 105/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
81/21 = 81 × 8/21 × 8 = 648/168 - Add the two like fractions:
105/168 + 648/168 = 105 + 648/168 = 753/168 - 753/168 simplified gives 251/56
- So, 5/8 + 81/21 = 251/56
In mixed form: 427/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/8+81/21 5/16+81/21 5/8+81/42 15/8+81/21 5/24+81/21 5/8+81/63 25/8+81/21 5/40+81/21 35/8+81/21 5/56+81/21