Add 12/15 and 25/21, Solve 12/15 + 1 4/21 as a fraction

Add 12/15 and 25/21

1^st number: 12/15, 2^nd number: 1 4/21

12/15 + 25/21 is 209/105.

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

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
12/15 = 12 × 7/15 × 7 = 84/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
25/21 = 25 × 5/21 × 5 = 125/105
Add the two like fractions:
84/105 + 125/105 = 84 + 125/105 = 209/105
So, 12/15 + 25/21 = 209/105
In mixed form: 1104/105

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