Add 20/12 and 21/18, Solve 1 8/12 + 1 3/18 as a fraction

Add 20/12 and 21/18

1^st number: 1 8/12, 2^nd number: 1 3/18

20/12 + 21/18 is 17/6.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 12 × 3 = 36,
20/12 = 20 × 3/12 × 3 = 60/36
Likewise, for the 2nd fraction, since 18 × 2 = 36,
21/18 = 21 × 2/18 × 2 = 42/36
Add the two like fractions:
60/36 + 42/36 = 60 + 42/36 = 102/36
102/36 simplified gives 17/6
So, 20/12 + 21/18 = 17/6
In mixed form: 25/6

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