Add 20/21 and 12/27
20/21 + 12/27 is 88/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 27 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 21 × 9 = 189,
20/21 = 20 × 9/21 × 9 = 180/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
12/27 = 12 × 7/27 × 7 = 84/189 - Add the two like fractions:
180/189 + 84/189 = 180 + 84/189 = 264/189 - 264/189 simplified gives 88/63
- So, 20/21 + 12/27 = 88/63
In mixed form: 125/63
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