Add 20/21 and 28/56
20/21 + 28/56 is 61/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
28/56 = 28 × 3/56 × 3 = 84/168 - Add the two like fractions:
160/168 + 84/168 = 160 + 84/168 = 244/168 - 244/168 simplified gives 61/42
- So, 20/21 + 28/56 = 61/42
In mixed form: 119/42
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