Add 21/30 and 3/12
21/30 + 3/12 is 19/20.
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,
3/12 = 3 × 5/12 × 5 = 15/60 - Add the two like fractions:
42/60 + 15/60 = 42 + 15/60 = 57/60 - 57/60 simplified gives 19/20
- So, 21/30 + 3/12 = 19/20
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