Add 21/8 and 25/81
1st number: 2 5/8, 2nd number: 25/81
21/8 + 25/81 is 1901/648.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 8 × 81 = 648,
21/8 = 21 × 81/8 × 81 = 1701/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
25/81 = 25 × 8/81 × 8 = 200/648 - Add the two like fractions:
1701/648 + 200/648 = 1701 + 200/648 = 1901/648 - So, 21/8 + 25/81 = 1901/648
In mixed form: 2605/648
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/8+25/81 21/8+50/81 21/16+25/81 63/8+25/81 21/8+75/81 21/24+25/81 21/40+25/81 21/56+25/81