Add 21/81 and 42/56
21/81 + 42/56 is 109/108.
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,
21/81 = 21 × 56/81 × 56 = 1176/4536 - Likewise, for the 2nd fraction, since 56 × 81 = 4536,
42/56 = 42 × 81/56 × 81 = 3402/4536 - Add the two like fractions:
1176/4536 + 3402/4536 = 1176 + 3402/4536 = 4578/4536 - 4578/4536 simplified gives 109/108
- So, 21/81 + 42/56 = 109/108
In mixed form: 11/108
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