Add 18/21 and 20/12, Solve 18/21 + 1 8/12 as a fraction

Add 18/21 and 20/12

1^st number: 18/21, 2^nd number: 1 8/12

18/21 + 20/12 is 53/21.

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,
18/21 = 18 × 4/21 × 4 = 72/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
20/12 = 20 × 7/12 × 7 = 140/84
Add the two like fractions:
72/84 + 140/84 = 72 + 140/84 = 212/84
212/84 simplified gives 53/21
So, 18/21 + 20/12 = 53/21
In mixed form: 211/21

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