Add 21/84 and 28/30
21/84 + 28/30 is 71/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 30 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 30 × 14 = 420,
28/30 = 28 × 14/30 × 14 = 392/420 - Add the two like fractions:
105/420 + 392/420 = 105 + 392/420 = 497/420 - 497/420 simplified gives 71/60
- So, 21/84 + 28/30 = 71/60
In mixed form: 111/60
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