Add 72/90 and 21/12
1st number: 72/90, 2nd number: 1 9/12
72/90 + 21/12 is 51/20.
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,
21/12 = 21 × 15/12 × 15 = 315/180 - Add the two like fractions:
144/180 + 315/180 = 144 + 315/180 = 459/180 - 459/180 simplified gives 51/20
- So, 72/90 + 21/12 = 51/20
In mixed form: 211/20
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