Add 21/12 and 15/35
1st number: 1 9/12, 2nd number: 15/35
21/12 + 15/35 is 61/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 35 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 12 × 35 = 420,
21/12 = 21 × 35/12 × 35 = 735/420 - Likewise, for the 2nd fraction, since 35 × 12 = 420,
15/35 = 15 × 12/35 × 12 = 180/420 - Add the two like fractions:
735/420 + 180/420 = 735 + 180/420 = 915/420 - 915/420 simplified gives 61/28
- So, 21/12 + 15/35 = 61/28
In mixed form: 25/28
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