Add 20/21 and 9/12
20/21 + 9/12 is 143/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
20/21 = 20 × 4/21 × 4 = 80/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
9/12 = 9 × 7/12 × 7 = 63/84 - Add the two like fractions:
80/84 + 63/84 = 80 + 63/84 = 143/84 - So, 20/21 + 9/12 = 143/84
In mixed form: 159/84
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