Add 81/21 and 8/15
1st number: 3 18/21, 2nd number: 8/15
81/21 + 8/15 is 461/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
81/21 = 81 × 5/21 × 5 = 405/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
8/15 = 8 × 7/15 × 7 = 56/105 - Add the two like fractions:
405/105 + 56/105 = 405 + 56/105 = 461/105 - So, 81/21 + 8/15 = 461/105
In mixed form: 441/105
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