Add 72/45 and 21/12
1st number: 1 27/45, 2nd number: 1 9/12
72/45 + 21/12 is 67/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
72/45 = 72 × 4/45 × 4 = 288/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
21/12 = 21 × 15/12 × 15 = 315/180 - Add the two like fractions:
288/180 + 315/180 = 288 + 315/180 = 603/180 - 603/180 simplified gives 67/20
- So, 72/45 + 21/12 = 67/20
In mixed form: 37/20
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