Add 12/21 and 18/27
12/21 + 18/27 is 26/21.
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,
12/21 = 12 × 9/21 × 9 = 108/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
18/27 = 18 × 7/27 × 7 = 126/189 - Add the two like fractions:
108/189 + 126/189 = 108 + 126/189 = 234/189 - 234/189 simplified gives 26/21
- So, 12/21 + 18/27 = 26/21
In mixed form: 15/21
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