Add 12/15 and 5/21
12/15 + 5/21 is 109/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
12/15 = 12 × 7/15 × 7 = 84/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
5/21 = 5 × 5/21 × 5 = 25/105 - Add the two like fractions:
84/105 + 25/105 = 84 + 25/105 = 109/105 - So, 12/15 + 5/21 = 109/105
In mixed form: 14/105
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