Add 15/12 and 42/70, Solve 1 3/12 + 42/70 as a fraction

Add 15/12 and 42/70

1^st number: 1 3/12, 2^nd number: 42/70

15/12 + 42/70 is 37/20.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 70 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 12 × 35 = 420,
15/12 = 15 × 35/12 × 35 = 525/420
Likewise, for the 2nd fraction, since 70 × 6 = 420,
42/70 = 42 × 6/70 × 6 = 252/420
Add the two like fractions:
525/420 + 252/420 = 525 + 252/420 = 777/420
777/420 simplified gives 37/20
So, 15/12 + 42/70 = 37/20
In mixed form: 117/20

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