Add 21/5 and 28/21
1st number: 4 1/5, 2nd number: 1 7/21
21/5 + 28/21 is 83/15.
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,
21/5 = 21 × 21/5 × 21 = 441/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
28/21 = 28 × 5/21 × 5 = 140/105 - Add the two like fractions:
441/105 + 140/105 = 441 + 140/105 = 581/105 - 581/105 simplified gives 83/15
- So, 21/5 + 28/21 = 83/15
In mixed form: 58/15
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