Add 20/36 and 80/21, Solve 20/36 + 3 17/21 as a fraction

Add 20/36 and 80/21

1^st number: 20/36, 2^nd number: 3 17/21

20/36 + 80/21 is 275/63.

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,
20/36 = 20 × 7/36 × 7 = 140/252
Likewise, for the 2nd fraction, since 21 × 12 = 252,
80/21 = 80 × 12/21 × 12 = 960/252
Add the two like fractions:
140/252 + 960/252 = 140 + 960/252 = 1100/252
1100/252 simplified gives 275/63
So, 20/36 + 80/21 = 275/63
In mixed form: 423/63

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