Add 7/21 and 7/9
7/21 + 7/9 is 10/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
7/21 = 7 × 3/21 × 3 = 21/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
7/9 = 7 × 7/9 × 7 = 49/63 - Add the two like fractions:
21/63 + 49/63 = 21 + 49/63 = 70/63 - 70/63 simplified gives 10/9
- So, 7/21 + 7/9 = 10/9
In mixed form: 11/9
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