Add 15/12 and 42/45, Solve 1 3/12 + 42/45 as a fraction

Add 15/12 and 42/45

1^st number: 1 3/12, 2^nd number: 42/45

15/12 + 42/45 is 131/60.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 45 is 180

Next, find the equivalent fraction of both fractional numbers with denominator 180
For the 1st fraction, since 12 × 15 = 180,
15/12 = 15 × 15/12 × 15 = 225/180
Likewise, for the 2nd fraction, since 45 × 4 = 180,
42/45 = 42 × 4/45 × 4 = 168/180
Add the two like fractions:
225/180 + 168/180 = 225 + 168/180 = 393/180
393/180 simplified gives 131/60
So, 15/12 + 42/45 = 131/60
In mixed form: 211/60

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