Add 21/9 and 28/20
1st number: 2 3/9, 2nd number: 1 8/20
21/9 + 28/20 is 56/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 9 × 20 = 180,
21/9 = 21 × 20/9 × 20 = 420/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
28/20 = 28 × 9/20 × 9 = 252/180 - Add the two like fractions:
420/180 + 252/180 = 420 + 252/180 = 672/180 - 672/180 simplified gives 56/15
- So, 21/9 + 28/20 = 56/15
In mixed form: 311/15
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