Add 28/9 and 81/21
1st number: 3 1/9, 2nd number: 3 18/21
28/9 + 81/21 is 439/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
28/9 = 28 × 7/9 × 7 = 196/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
81/21 = 81 × 3/21 × 3 = 243/63 - Add the two like fractions:
196/63 + 243/63 = 196 + 243/63 = 439/63 - So, 28/9 + 81/21 = 439/63
In mixed form: 661/63
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