Add 54/15 and 27/42, Solve 3 9/15 + 27/42 as a fraction

Add 54/15 and 27/42

1^st number: 3 9/15, 2^nd number: 27/42

54/15 + 27/42 is 297/70.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 42 is 210

Next, find the equivalent fraction of both fractional numbers with denominator 210
For the 1st fraction, since 15 × 14 = 210,
54/15 = 54 × 14/15 × 14 = 756/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
27/42 = 27 × 5/42 × 5 = 135/210
Add the two like fractions:
756/210 + 135/210 = 756 + 135/210 = 891/210
891/210 simplified gives 297/70
So, 54/15 + 27/42 = 297/70
In mixed form: 417/70

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