Add 56/81 and 21/56
56/81 + 21/56 is 691/648.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 56 is 4536
Next, find the equivalent fraction of both fractional numbers with denominator 4536 - For the 1st fraction, since 81 × 56 = 4536,
56/81 = 56 × 56/81 × 56 = 3136/4536 - Likewise, for the 2nd fraction, since 56 × 81 = 4536,
21/56 = 21 × 81/56 × 81 = 1701/4536 - Add the two like fractions:
3136/4536 + 1701/4536 = 3136 + 1701/4536 = 4837/4536 - 4837/4536 simplified gives 691/648
- So, 56/81 + 21/56 = 691/648
In mixed form: 143/648
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