Add 3/9 and 21/28
3/9 + 21/28 is 13/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 28 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 9 × 28 = 252,
3/9 = 3 × 28/9 × 28 = 84/252 - Likewise, for the 2nd fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Add the two like fractions:
84/252 + 189/252 = 84 + 189/252 = 273/252 - 273/252 simplified gives 13/12
- So, 3/9 + 21/28 = 13/12
In mixed form: 11/12
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