Add 21/84 and 28/35
21/84 + 28/35 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 35 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 35 × 12 = 420,
28/35 = 28 × 12/35 × 12 = 336/420 - Add the two like fractions:
105/420 + 336/420 = 105 + 336/420 = 441/420 - 441/420 simplified gives 21/20
- So, 21/84 + 28/35 = 21/20
In mixed form: 11/20
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