Add 56/36 and 7/21, Solve 1 20/36 + 7/21 as a fraction

Add 56/36 and 7/21

1^st number: 1 20/36, 2^nd number: 7/21

56/36 + 7/21 is 17/9.

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,
56/36 = 56 × 7/36 × 7 = 392/252
Likewise, for the 2nd fraction, since 21 × 12 = 252,
7/21 = 7 × 12/21 × 12 = 84/252
Add the two like fractions:
392/252 + 84/252 = 392 + 84/252 = 476/252
476/252 simplified gives 17/9
So, 56/36 + 7/21 = 17/9
In mixed form: 18/9

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