Add 21/12 and 81/90
1st number: 1 9/12, 2nd number: 81/90
21/12 + 81/90 is 53/20.
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,
81/90 = 81 × 2/90 × 2 = 162/180 - Add the two like fractions:
315/180 + 162/180 = 315 + 162/180 = 477/180 - 477/180 simplified gives 53/20
- So, 21/12 + 81/90 = 53/20
In mixed form: 213/20
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