Add 3/15 and 84/63, Solve 3/15 + 1 21/63 as a fraction

Add 3/15 and 84/63

1^st number: 3/15, 2^nd number: 1 21/63

3/15 + 84/63 is 23/15.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 63 is 315

Next, find the equivalent fraction of both fractional numbers with denominator 315
For the 1st fraction, since 15 × 21 = 315,
3/15 = 3 × 21/15 × 21 = 63/315
Likewise, for the 2nd fraction, since 63 × 5 = 315,
84/63 = 84 × 5/63 × 5 = 420/315
Add the two like fractions:
63/315 + 420/315 = 63 + 420/315 = 483/315
483/315 simplified gives 23/15
So, 3/15 + 84/63 = 23/15
In mixed form: 18/15

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