Add 21/56 and 18/20
21/56 + 18/20 is 51/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 20 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 20 × 14 = 280,
18/20 = 18 × 14/20 × 14 = 252/280 - Add the two like fractions:
105/280 + 252/280 = 105 + 252/280 = 357/280 - 357/280 simplified gives 51/40
- So, 21/56 + 18/20 = 51/40
In mixed form: 111/40
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