Add 21/15 and 20/21
1st number: 1 6/15, 2nd number: 20/21
21/15 + 20/21 is 247/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
21/15 = 21 × 7/15 × 7 = 147/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
20/21 = 20 × 5/21 × 5 = 100/105 - Add the two like fractions:
147/105 + 100/105 = 147 + 100/105 = 247/105 - So, 21/15 + 20/21 = 247/105
In mixed form: 237/105
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