Add 21/63 and 28/21
1st number: 21/63, 2nd number: 1 7/21
21/63 + 28/21 is 5/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 63 × 1 = 63,
21/63 = 21 × 1/63 × 1 = 21/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
28/21 = 28 × 3/21 × 3 = 84/63 - Add the two like fractions:
21/63 + 84/63 = 21 + 84/63 = 105/63 - 105/63 simplified gives 5/3
- So, 21/63 + 28/21 = 5/3
In mixed form: 12/3
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