Add 84/72 and 21/81
1st number: 1 12/72, 2nd number: 21/81
84/72 + 21/81 is 77/54.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 72 × 9 = 648,
84/72 = 84 × 9/72 × 9 = 756/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
21/81 = 21 × 8/81 × 8 = 168/648 - Add the two like fractions:
756/648 + 168/648 = 756 + 168/648 = 924/648 - 924/648 simplified gives 77/54
- So, 84/72 + 21/81 = 77/54
In mixed form: 123/54
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