Add 21/30 and 12/20
21/30 + 12/20 is 13/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 20 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 20 × 3 = 60,
12/20 = 12 × 3/20 × 3 = 36/60 - Add the two like fractions:
42/60 + 36/60 = 42 + 36/60 = 78/60 - 78/60 simplified gives 13/10
- So, 21/30 + 12/20 = 13/10
In mixed form: 13/10
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