Add 21/30 and 21/80
21/30 + 21/80 is 77/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 80 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 30 × 8 = 240,
21/30 = 21 × 8/30 × 8 = 168/240 - Likewise, for the 2nd fraction, since 80 × 3 = 240,
21/80 = 21 × 3/80 × 3 = 63/240 - Add the two like fractions:
168/240 + 63/240 = 168 + 63/240 = 231/240 - 231/240 simplified gives 77/80
- So, 21/30 + 21/80 = 77/80
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30+21/80 21/30+42/80 21/60+21/80 63/30+21/80 21/30+63/80 21/90+21/80