Add 45/12 and 27/18, Solve 3 9/12 + 1 9/18 as a fraction

Add 45/12 and 27/18

1^st number: 3 9/12, 2^nd number: 1 9/18

45/12 + 27/18 is 21/4.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 12 × 3 = 36,
45/12 = 45 × 3/12 × 3 = 135/36
Likewise, for the 2nd fraction, since 18 × 2 = 36,
27/18 = 27 × 2/18 × 2 = 54/36
Add the two like fractions:
135/36 + 54/36 = 135 + 54/36 = 189/36
189/36 simplified gives 21/4
So, 45/12 + 27/18 = 21/4
In mixed form: 51/4

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