Add 28/15 and 21/63, Solve 1 13/15 + 21/63 as a fraction

Add 28/15 and 21/63

1^st number: 1 13/15, 2^nd number: 21/63

28/15 + 21/63 is 11/5.

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,
28/15 = 28 × 21/15 × 21 = 588/315
Likewise, for the 2nd fraction, since 63 × 5 = 315,
21/63 = 21 × 5/63 × 5 = 105/315
Add the two like fractions:
588/315 + 105/315 = 588 + 105/315 = 693/315
693/315 simplified gives 11/5
So, 28/15 + 21/63 = 11/5
In mixed form: 21/5

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