Add 21/56 and 54/70
21/56 + 54/70 is 321/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 56 × 5 = 280,
21/56 = 21 × 5/56 × 5 = 105/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
54/70 = 54 × 4/70 × 4 = 216/280 - Add the two like fractions:
105/280 + 216/280 = 105 + 216/280 = 321/280 - So, 21/56 + 54/70 = 321/280
In mixed form: 141/280
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/56+54/70 63/56+54/70