Add 20/21 and 28/5
1st number: 20/21, 2nd number: 5 3/5
20/21 + 28/5 is 688/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Likewise, for the 2nd fraction, since 5 × 21 = 105,
28/5 = 28 × 21/5 × 21 = 588/105 - Add the two like fractions:
100/105 + 588/105 = 100 + 588/105 = 688/105 - So, 20/21 + 28/5 = 688/105
In mixed form: 658/105
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