Add 21/90 and 2/80
21/90 + 2/80 is 31/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 80 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 90 × 8 = 720,
21/90 = 21 × 8/90 × 8 = 168/720 - Likewise, for the 2nd fraction, since 80 × 9 = 720,
2/80 = 2 × 9/80 × 9 = 18/720 - Add the two like fractions:
168/720 + 18/720 = 168 + 18/720 = 186/720 - 186/720 simplified gives 31/120
- So, 21/90 + 2/80 = 31/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/90+2/80 21/90+4/80 63/90+2/80 21/90+6/80 21/90+10/80 21/90+14/80