Add 28/36 and 20/21
28/36 + 20/21 is 109/63.
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,
28/36 = 28 × 7/36 × 7 = 196/252 - Likewise, for the 2nd fraction, since 21 × 12 = 252,
20/21 = 20 × 12/21 × 12 = 240/252 - Add the two like fractions:
196/252 + 240/252 = 196 + 240/252 = 436/252 - 436/252 simplified gives 109/63
- So, 28/36 + 20/21 = 109/63
In mixed form: 146/63
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