Add 81/12 and 20/90
1st number: 6 9/12, 2nd number: 20/90
81/12 + 20/90 is 251/36.
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,
81/12 = 81 × 15/12 × 15 = 1215/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
20/90 = 20 × 2/90 × 2 = 40/180 - Add the two like fractions:
1215/180 + 40/180 = 1215 + 40/180 = 1255/180 - 1255/180 simplified gives 251/36
- So, 81/12 + 20/90 = 251/36
In mixed form: 635/36
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