Add 20/28 and 21/9
1st number: 20/28, 2nd number: 2 3/9
20/28 + 21/9 is 64/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 9 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
20/28 = 20 × 9/28 × 9 = 180/252 - Likewise, for the 2nd fraction, since 9 × 28 = 252,
21/9 = 21 × 28/9 × 28 = 588/252 - Add the two like fractions:
180/252 + 588/252 = 180 + 588/252 = 768/252 - 768/252 simplified gives 64/21
- So, 20/28 + 21/9 = 64/21
In mixed form: 31/21
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