Add 12/16 and 9/21
12/16 + 9/21 is 33/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 21 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 16 × 21 = 336,
12/16 = 12 × 21/16 × 21 = 252/336 - Likewise, for the 2nd fraction, since 21 × 16 = 336,
9/21 = 9 × 16/21 × 16 = 144/336 - Add the two like fractions:
252/336 + 144/336 = 252 + 144/336 = 396/336 - 396/336 simplified gives 33/28
- So, 12/16 + 9/21 = 33/28
In mixed form: 15/28
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