Add 21/28 and 35/30
1st number: 21/28, 2nd number: 1 5/30
21/28 + 35/30 is 23/12.
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,
21/28 = 21 × 15/28 × 15 = 315/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
35/30 = 35 × 14/30 × 14 = 490/420 - Add the two like fractions:
315/420 + 490/420 = 315 + 490/420 = 805/420 - 805/420 simplified gives 23/12
- So, 21/28 + 35/30 = 23/12
In mixed form: 111/12
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