Add 21/36 and 28/21
1st number: 21/36, 2nd number: 1 7/21
21/36 + 28/21 is 23/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
21/36 = 21 × 7/36 × 7 = 147/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
28/21 = 28 × 12/21 × 12 = 336/252 - Add the two like fractions:
147/252 + 336/252 = 147 + 336/252 = 483/252 - 483/252 simplified gives 23/12
- So, 21/36 + 28/21 = 23/12
In mixed form: 111/12
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