Add 20/12 and 81/90
1st number: 1 8/12, 2nd number: 81/90
20/12 + 81/90 is 77/30.
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,
20/12 = 20 × 15/12 × 15 = 300/180 - Likewise, for the 2nd fraction, since 90 × 2 = 180,
81/90 = 81 × 2/90 × 2 = 162/180 - Add the two like fractions:
300/180 + 162/180 = 300 + 162/180 = 462/180 - 462/180 simplified gives 77/30
- So, 20/12 + 81/90 = 77/30
In mixed form: 217/30
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