Add 21/35 and 9/12
21/35 + 9/12 is 27/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 35 × 12 = 420,
21/35 = 21 × 12/35 × 12 = 252/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
9/12 = 9 × 35/12 × 35 = 315/420 - Add the two like fractions:
252/420 + 315/420 = 252 + 315/420 = 567/420 - 567/420 simplified gives 27/20
- So, 21/35 + 9/12 = 27/20
In mixed form: 17/20
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