Add 21/30 and 18/12
1st number: 21/30, 2nd number: 1 6/12
21/30 + 18/12 is 11/5.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 12 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 30 × 2 = 60,
21/30 = 21 × 2/30 × 2 = 42/60 - Likewise, for the 2nd fraction, since 12 × 5 = 60,
18/12 = 18 × 5/12 × 5 = 90/60 - Add the two like fractions:
42/60 + 90/60 = 42 + 90/60 = 132/60 - 132/60 simplified gives 11/5
- So, 21/30 + 18/12 = 11/5
In mixed form: 21/5
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