Add 20/21 and 5/7
20/21 + 5/7 is 5/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
20/21 = 20 × 1/21 × 1 = 20/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
5/7 = 5 × 3/7 × 3 = 15/21 - Add the two like fractions:
20/21 + 15/21 = 20 + 15/21 = 35/21 - 35/21 simplified gives 5/3
- So, 20/21 + 5/7 = 5/3
In mixed form: 12/3
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