Add 1/3 and 20/21
1/3 + 20/21 is 9/7.
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,
1/3 = 1 × 7/3 × 7 = 7/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
20/21 = 20 × 1/21 × 1 = 20/21 - Add the two like fractions:
7/21 + 20/21 = 7 + 20/21 = 27/21 - 27/21 simplified gives 9/7
- So, 1/3 + 20/21 = 9/7
In mixed form: 12/7
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