Add 12/9 and 21/30
1st number: 1 3/9, 2nd number: 21/30
12/9 + 21/30 is 61/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 30 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 9 × 10 = 90,
12/9 = 12 × 10/9 × 10 = 120/90 - Likewise, for the 2nd fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Add the two like fractions:
120/90 + 63/90 = 120 + 63/90 = 183/90 - 183/90 simplified gives 61/30
- So, 12/9 + 21/30 = 61/30
In mixed form: 21/30
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