Add 20/56 and 28/21
1st number: 20/56, 2nd number: 1 7/21
20/56 + 28/21 is 71/42.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
20/56 = 20 × 3/56 × 3 = 60/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
28/21 = 28 × 8/21 × 8 = 224/168 - Add the two like fractions:
60/168 + 224/168 = 60 + 224/168 = 284/168 - 284/168 simplified gives 71/42
- So, 20/56 + 28/21 = 71/42
In mixed form: 129/42
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