Add 84/4 and 28/21
1st number: 21 0/4, 2nd number: 1 7/21
84/4 + 28/21 is 67/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
84/4 = 84 × 21/4 × 21 = 1764/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
28/21 = 28 × 4/21 × 4 = 112/84 - Add the two like fractions:
1764/84 + 112/84 = 1764 + 112/84 = 1876/84 - 1876/84 simplified gives 67/3
- So, 84/4 + 28/21 = 67/3
In mixed form: 221/3
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