Add 20/21 and 21/63
20/21 + 21/63 is 9/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 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 63 × 1 = 63,
21/63 = 21 × 1/63 × 1 = 21/63 - Add the two like fractions:
60/63 + 21/63 = 60 + 21/63 = 81/63 - 81/63 simplified gives 9/7
- So, 20/21 + 21/63 = 9/7
In mixed form: 12/7
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