Add 27/21 and 18/15, Solve 1 6/21 + 1 3/15 as a fraction

Add 27/21 and 18/15

1^st number: 1 6/21, 2^nd number: 1 3/15

27/21 + 18/15 is 87/35.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
27/21 = 27 × 5/21 × 5 = 135/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
18/15 = 18 × 7/15 × 7 = 126/105
Add the two like fractions:
135/105 + 126/105 = 135 + 126/105 = 261/105
261/105 simplified gives 87/35
So, 27/21 + 18/15 = 87/35
In mixed form: 217/35

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