Add 27/36 and 40/21, Solve 27/36 + 1 19/21 as a fraction

Add 27/36 and 40/21

1^st number: 27/36, 2^nd number: 1 19/21

27/36 + 40/21 is 223/84.

Find the least common denominator or LCM of the two denominators:
LCM of 36 and 21 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 36 × 7 = 252,
27/36 = 27 × 7/36 × 7 = 189/252
Likewise, for the 2nd fraction, since 21 × 12 = 252,
40/21 = 40 × 12/21 × 12 = 480/252
Add the two like fractions:
189/252 + 480/252 = 189 + 480/252 = 669/252
669/252 simplified gives 223/84
So, 27/36 + 40/21 = 223/84
In mixed form: 255/84

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