Add 12/21 and 5/7
12/21 + 5/7 is 9/7.
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,
12/21 = 12 × 1/21 × 1 = 12/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
5/7 = 5 × 3/7 × 3 = 15/21 - Add the two like fractions:
12/21 + 15/21 = 12 + 15/21 = 27/21 - 27/21 simplified gives 9/7
- So, 12/21 + 5/7 = 9/7
In mixed form: 12/7
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