Add 21/30 and 28/84
21/30 + 28/84 is 31/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 84 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 84 × 5 = 420,
28/84 = 28 × 5/84 × 5 = 140/420 - Add the two like fractions:
294/420 + 140/420 = 294 + 140/420 = 434/420 - 434/420 simplified gives 31/30
- So, 21/30 + 28/84 = 31/30
In mixed form: 11/30
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