Add 3/84 and 27/15, Solve 3/84 + 1 12/15 as a fraction

Add 3/84 and 27/15

1^st number: 3/84, 2^nd number: 1 12/15

3/84 + 27/15 is 257/140.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
3/84 = 3 × 5/84 × 5 = 15/420
Likewise, for the 2nd fraction, since 15 × 28 = 420,
27/15 = 27 × 28/15 × 28 = 756/420
Add the two like fractions:
15/420 + 756/420 = 15 + 756/420 = 771/420
771/420 simplified gives 257/140
So, 3/84 + 27/15 = 257/140
In mixed form: 1117/140

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