Add 27/70 and 45/12, Solve 27/70 + 3 9/12 as a fraction

Add 27/70 and 45/12

1^st number: 27/70, 2^nd number: 3 9/12

27/70 + 45/12 is 579/140.

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

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 70 × 6 = 420,
27/70 = 27 × 6/70 × 6 = 162/420
Likewise, for the 2nd fraction, since 12 × 35 = 420,
45/12 = 45 × 35/12 × 35 = 1575/420
Add the two like fractions:
162/420 + 1575/420 = 162 + 1575/420 = 1737/420
1737/420 simplified gives 579/140
So, 27/70 + 45/12 = 579/140
In mixed form: 419/140

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