Add 20/21 and 8/9
20/21 + 8/9 is 116/63.
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,
20/21 = 20 × 3/21 × 3 = 60/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
8/9 = 8 × 7/9 × 7 = 56/63 - Add the two like fractions:
60/63 + 56/63 = 60 + 56/63 = 116/63 - So, 20/21 + 8/9 = 116/63
In mixed form: 153/63
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