Add 6/9 and 6/21
6/9 + 6/21 is 20/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
6/9 = 6 × 7/9 × 7 = 42/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
6/21 = 6 × 3/21 × 3 = 18/63 - Add the two like fractions:
42/63 + 18/63 = 42 + 18/63 = 60/63 - 60/63 simplified gives 20/21
- So, 6/9 + 6/21 = 20/21
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