Add 27/21 and 20/45, Solve 1 6/21 + 20/45 as a fraction

Add 27/21 and 20/45

1^st number: 1 6/21, 2^nd number: 20/45

27/21 + 20/45 is 109/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 21 × 15 = 315,
27/21 = 27 × 15/21 × 15 = 405/315
Likewise, for the 2nd fraction, since 45 × 7 = 315,
20/45 = 20 × 7/45 × 7 = 140/315
Add the two like fractions:
405/315 + 140/315 = 405 + 140/315 = 545/315
545/315 simplified gives 109/63
So, 27/21 + 20/45 = 109/63
In mixed form: 146/63

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