Add 14/12 and 54/15, Solve 1 2/12 + 3 9/15 as a fraction

Add 14/12 and 54/15

1^st number: 1 2/12, 2^nd number: 3 9/15

14/12 + 54/15 is 143/30.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 15 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 12 × 5 = 60,
14/12 = 14 × 5/12 × 5 = 70/60
Likewise, for the 2nd fraction, since 15 × 4 = 60,
54/15 = 54 × 4/15 × 4 = 216/60
Add the two like fractions:
70/60 + 216/60 = 70 + 216/60 = 286/60
286/60 simplified gives 143/30
So, 14/12 + 54/15 = 143/30
In mixed form: 423/30

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