Add 21/36 and 54/21, Solve 21/36 + 2 12/21 as a fraction

Add 21/36 and 54/21

1^st number: 21/36, 2^nd number: 2 12/21

21/36 + 54/21 is 265/84.

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,
21/36 = 21 × 7/36 × 7 = 147/252
Likewise, for the 2nd fraction, since 21 × 12 = 252,
54/21 = 54 × 12/21 × 12 = 648/252
Add the two like fractions:
147/252 + 648/252 = 147 + 648/252 = 795/252
795/252 simplified gives 265/84
So, 21/36 + 54/21 = 265/84
In mixed form: 313/84

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