Add 72/21 and 20/56
1st number: 3 9/21, 2nd number: 20/56
72/21 + 20/56 is 53/14.
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,
72/21 = 72 × 8/21 × 8 = 576/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
20/56 = 20 × 3/56 × 3 = 60/168 - Add the two like fractions:
576/168 + 60/168 = 576 + 60/168 = 636/168 - 636/168 simplified gives 53/14
- So, 72/21 + 20/56 = 53/14
In mixed form: 311/14
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