Add 20/30 and 21/28
20/30 + 21/28 is 17/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
20/30 = 20 × 14/30 × 14 = 280/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Add the two like fractions:
280/420 + 315/420 = 280 + 315/420 = 595/420 - 595/420 simplified gives 17/12
- So, 20/30 + 21/28 = 17/12
In mixed form: 15/12
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