Add 72/90 and 81/12
1st number: 72/90, 2nd number: 6 9/12
72/90 + 81/12 is 151/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
72/90 = 72 × 2/90 × 2 = 144/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
81/12 = 81 × 15/12 × 15 = 1215/180 - Add the two like fractions:
144/180 + 1215/180 = 144 + 1215/180 = 1359/180 - 1359/180 simplified gives 151/20
- So, 72/90 + 81/12 = 151/20
In mixed form: 711/20
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