Add 20/21 and 49/12, Solve 20/21 + 4 1/12 as a fraction

Add 20/21 and 49/12

1^st number: 20/21, 2^nd number: 4 1/12

20/21 + 49/12 is 141/28.

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,
49/12 = 49 × 7/12 × 7 = 343/84
Add the two like fractions:
80/84 + 343/84 = 80 + 343/84 = 423/84
423/84 simplified gives 141/28
So, 20/21 + 49/12 = 141/28
In mixed form: 51/28

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