Add 20/12 and 3/21, Solve 1 8/12 + 3/21 as a fraction

Add 20/12 and 3/21

1^st number: 1 8/12, 2^nd number: 3/21

20/12 + 3/21 is 38/21.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
3/21 = 3 × 4/21 × 4 = 12/84
Add the two like fractions:
140/84 + 12/84 = 140 + 12/84 = 152/84
152/84 simplified gives 38/21
So, 20/12 + 3/21 = 38/21
In mixed form: 117/21

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