Add 84/5 and 28/21
1st number: 16 4/5, 2nd number: 1 7/21
84/5 + 28/21 is 272/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
84/5 = 84 × 21/5 × 21 = 1764/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Add the two like fractions:
1764/105 + 140/105 = 1764 + 140/105 = 1904/105 - 1904/105 simplified gives 272/15
- So, 84/5 + 28/21 = 272/15
In mixed form: 182/15
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