Add 27/21 and 45/12, Solve 1 6/21 + 3 9/12 as a fraction

Add 27/21 and 45/12

1^st number: 1 6/21, 2^nd number: 3 9/12

27/21 + 45/12 is 141/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
27/21 = 27 × 4/21 × 4 = 108/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
45/12 = 45 × 7/12 × 7 = 315/84
Add the two like fractions:
108/84 + 315/84 = 108 + 315/84 = 423/84
423/84 simplified gives 141/28
So, 27/21 + 45/12 = 141/28
In mixed form: 51/28

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