Add 21/27 and 28/63
21/27 + 28/63 is 11/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 63 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 27 × 7 = 189,
21/27 = 21 × 7/27 × 7 = 147/189 - Likewise, for the 2nd fraction, since 63 × 3 = 189,
28/63 = 28 × 3/63 × 3 = 84/189 - Add the two like fractions:
147/189 + 84/189 = 147 + 84/189 = 231/189 - 231/189 simplified gives 11/9
- So, 21/27 + 28/63 = 11/9
In mixed form: 12/9
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