Add 12/15 and 42/27, Solve 12/15 + 1 15/27 as a fraction

Add 12/15 and 42/27

1^st number: 12/15, 2^nd number: 1 15/27

12/15 + 42/27 is 106/45.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 27 is 135

Next, find the equivalent fraction of both fractional numbers with denominator 135
For the 1st fraction, since 15 × 9 = 135,
12/15 = 12 × 9/15 × 9 = 108/135
Likewise, for the 2nd fraction, since 27 × 5 = 135,
42/27 = 42 × 5/27 × 5 = 210/135
Add the two like fractions:
108/135 + 210/135 = 108 + 210/135 = 318/135
318/135 simplified gives 106/45
So, 12/15 + 42/27 = 106/45
In mixed form: 216/45

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