Add 72/21 and 21/81
1st number: 3 9/21, 2nd number: 21/81
72/21 + 21/81 is 697/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
72/21 = 72 × 27/21 × 27 = 1944/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
21/81 = 21 × 7/81 × 7 = 147/567 - Add the two like fractions:
1944/567 + 147/567 = 1944 + 147/567 = 2091/567 - 2091/567 simplified gives 697/189
- So, 72/21 + 21/81 = 697/189
In mixed form: 3130/189
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