Add 1/3 and 18/21
1/3 + 18/21 is 25/21.
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,
1/3 = 1 × 7/3 × 7 = 7/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
18/21 = 18 × 1/21 × 1 = 18/21 - Add the two like fractions:
7/21 + 18/21 = 7 + 18/21 = 25/21 - So, 1/3 + 18/21 = 25/21
In mixed form: 14/21
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