Add 12/28 and 21/30
12/28 + 21/30 is 79/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 28 × 15 = 420,
12/28 = 12 × 15/28 × 15 = 180/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420 - Add the two like fractions:
180/420 + 294/420 = 180 + 294/420 = 474/420 - 474/420 simplified gives 79/70
- So, 12/28 + 21/30 = 79/70
In mixed form: 19/70
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