Add 81/12 and 21/30
1st number: 6 9/12, 2nd number: 21/30
81/12 + 21/30 is 149/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 30 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
81/12 = 81 × 5/12 × 5 = 405/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Add the two like fractions:
405/60 + 42/60 = 405 + 42/60 = 447/60 - 447/60 simplified gives 149/20
- So, 81/12 + 21/30 = 149/20
In mixed form: 79/20
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