Add 12/21 and 72/84
12/21 + 72/84 is 10/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
12/21 = 12 × 4/21 × 4 = 48/84 - Likewise, for the 2nd fraction, since 84 × 1 = 84,
72/84 = 72 × 1/84 × 1 = 72/84 - Add the two like fractions:
48/84 + 72/84 = 48 + 72/84 = 120/84 - 120/84 simplified gives 10/7
- So, 12/21 + 72/84 = 10/7
In mixed form: 13/7
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