Add 72/21 and 18/27
1st number: 3 9/21, 2nd number: 18/27
72/21 + 18/27 is 86/21.
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,
72/21 = 72 × 9/21 × 9 = 648/189 - Likewise, for the 2nd fraction, since 27 × 7 = 189,
18/27 = 18 × 7/27 × 7 = 126/189 - Add the two like fractions:
648/189 + 126/189 = 648 + 126/189 = 774/189 - 774/189 simplified gives 86/21
- So, 72/21 + 18/27 = 86/21
In mixed form: 42/21
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