Add 21/12 and 28/90
1st number: 1 9/12, 2nd number: 28/90
21/12 + 28/90 is 371/180.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 90 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
21/12 = 21 × 15/12 × 15 = 315/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
28/90 = 28 × 2/90 × 2 = 56/180 - Add the two like fractions:
315/180 + 56/180 = 315 + 56/180 = 371/180 - So, 21/12 + 28/90 = 371/180
In mixed form: 211/180
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