Add 21/12 and 84/30
1st number: 1 9/12, 2nd number: 2 24/30
21/12 + 84/30 is 91/20.
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,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 30 × 2 = 60,
84/30 = 84 × 2/30 × 2 = 168/60 - Add the two like fractions:
105/60 + 168/60 = 105 + 168/60 = 273/60 - 273/60 simplified gives 91/20
- So, 21/12 + 84/30 = 91/20
In mixed form: 411/20
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