Add 21/30 and 9/28
21/30 + 9/28 is 143/140.
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,
21/30 = 21 × 14/30 × 14 = 294/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
9/28 = 9 × 15/28 × 15 = 135/420 - Add the two like fractions:
294/420 + 135/420 = 294 + 135/420 = 429/420 - 429/420 simplified gives 143/140
- So, 21/30 + 9/28 = 143/140
In mixed form: 13/140
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