Add 20/28 and 21/18, Solve 20/28 + 1 3/18 as a fraction

Add 20/28 and 21/18

1^st number: 20/28, 2^nd number: 1 3/18

20/28 + 21/18 is 79/42.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 18 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 28 × 9 = 252,
20/28 = 20 × 9/28 × 9 = 180/252
Likewise, for the 2nd fraction, since 18 × 14 = 252,
21/18 = 21 × 14/18 × 14 = 294/252
Add the two like fractions:
180/252 + 294/252 = 180 + 294/252 = 474/252
474/252 simplified gives 79/42
So, 20/28 + 21/18 = 79/42
In mixed form: 137/42

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