Add 9/14 and 15/21, Solve 9/14 + 15/21 as a fraction

Add 9/14 and 15/21

9/14 + 15/21 is 19/14.

Find the least common denominator or LCM of the two denominators:
LCM of 14 and 21 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 14 × 3 = 42,
9/14 = 9 × 3/14 × 3 = 27/42
Likewise, for the 2nd fraction, since 21 × 2 = 42,
15/21 = 15 × 2/21 × 2 = 30/42
Add the two like fractions:
27/42 + 30/42 = 27 + 30/42 = 57/42
57/42 simplified gives 19/14
So, 9/14 + 15/21 = 19/14
In mixed form: 15/14

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