Add 81/56 and 21/70
1st number: 1 25/56, 2nd number: 21/70
81/56 + 21/70 is 489/280.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 56 × 5 = 280,
81/56 = 81 × 5/56 × 5 = 405/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Add the two like fractions:
405/280 + 84/280 = 405 + 84/280 = 489/280 - So, 81/56 + 21/70 = 489/280
In mixed form: 1209/280
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