Add 4/21 and 20/12, Solve 4/21 + 1 8/12 as a fraction

Add 4/21 and 20/12

1^st number: 4/21, 2^nd number: 1 8/12

4/21 + 20/12 is 13/7.

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,
4/21 = 4 × 4/21 × 4 = 16/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84
Add the two like fractions:
16/84 + 140/84 = 16 + 140/84 = 156/84
156/84 simplified gives 13/7
So, 4/21 + 20/12 = 13/7
In mixed form: 16/7

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