Add 15/18 and 27/21, Solve 15/18 + 1 6/21 as a fraction

Add 15/18 and 27/21

1^st number: 15/18, 2^nd number: 1 6/21

15/18 + 27/21 is 89/42.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
27/21 = 27 × 6/21 × 6 = 162/126
Add the two like fractions:
105/126 + 162/126 = 105 + 162/126 = 267/126
267/126 simplified gives 89/42
So, 15/18 + 27/21 = 89/42
In mixed form: 25/42

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