Add 20/21 and 7/12, Solve 20/21 + 7/12 as a fraction

Add 20/21 and 7/12

20/21 + 7/12 is 43/28.

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,
7/12 = 7 × 7/12 × 7 = 49/84
Add the two like fractions:
80/84 + 49/84 = 80 + 49/84 = 129/84
129/84 simplified gives 43/28
So, 20/21 + 7/12 = 43/28
In mixed form: 115/28

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