Add 56/81 and 15/40
56/81 + 15/40 is 691/648.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 40 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 81 × 40 = 3240,
56/81 = 56 × 40/81 × 40 = 2240/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
15/40 = 15 × 81/40 × 81 = 1215/3240 - Add the two like fractions:
2240/3240 + 1215/3240 = 2240 + 1215/3240 = 3455/3240 - 3455/3240 simplified gives 691/648
- So, 56/81 + 15/40 = 691/648
In mixed form: 143/648
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