Add 18/15 and 54/42, Solve 1 3/15 + 1 12/42 as a fraction

Add 18/15 and 54/42

1^st number: 1 3/15, 2^nd number: 1 12/42

18/15 + 54/42 is 87/35.

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,
18/15 = 18 × 14/15 × 14 = 252/210
Likewise, for the 2nd fraction, since 42 × 5 = 210,
54/42 = 54 × 5/42 × 5 = 270/210
Add the two like fractions:
252/210 + 270/210 = 252 + 270/210 = 522/210
522/210 simplified gives 87/35
So, 18/15 + 54/42 = 87/35
In mixed form: 217/35

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