Add 21/12 and 81/15
1st number: 1 9/12, 2nd number: 5 6/15
21/12 + 81/15 is 143/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
81/15 = 81 × 4/15 × 4 = 324/60 - Add the two like fractions:
105/60 + 324/60 = 105 + 324/60 = 429/60 - 429/60 simplified gives 143/20
- So, 21/12 + 81/15 = 143/20
In mixed form: 73/20
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