Add 15/12 and 72/20, Solve 1 3/12 + 3 12/20 as a fraction

Add 15/12 and 72/20

1^st number: 1 3/12, 2^nd number: 3 12/20

15/12 + 72/20 is 97/20.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 20 is 60

Next, find the equivalent fraction of both fractional numbers with denominator 60
For the 1st fraction, since 12 × 5 = 60,
15/12 = 15 × 5/12 × 5 = 75/60
Likewise, for the 2nd fraction, since 20 × 3 = 60,
72/20 = 72 × 3/20 × 3 = 216/60
Add the two like fractions:
75/60 + 216/60 = 75 + 216/60 = 291/60
291/60 simplified gives 97/20
So, 15/12 + 72/20 = 97/20
In mixed form: 417/20

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