Add 21/3 and 20/21
1st number: 7 0/3, 2nd number: 20/21
21/3 + 20/21 is 167/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
21/3 = 21 × 7/3 × 7 = 147/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
20/21 = 20 × 1/21 × 1 = 20/21 - Add the two like fractions:
147/21 + 20/21 = 147 + 20/21 = 167/21 - So, 21/3 + 20/21 = 167/21
In mixed form: 720/21
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