Add 12/15 and 63/21, Solve 12/15 + 3 0/21 as a fraction

Add 12/15 and 63/21

1^st number: 12/15, 2^nd number: 3 0/21

12/15 + 63/21 is 19/5.

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,
63/21 = 63 × 5/21 × 5 = 315/105
Add the two like fractions:
84/105 + 315/105 = 84 + 315/105 = 399/105
399/105 simplified gives 19/5
So, 12/15 + 63/21 = 19/5
In mixed form: 34/5

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