Add 15/21 and 28/16, Solve 15/21 + 1 12/16 as a fraction

Add 15/21 and 28/16

1^st number: 15/21, 2^nd number: 1 12/16

15/21 + 28/16 is 69/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 16 is 336

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 21 × 16 = 336,
15/21 = 15 × 16/21 × 16 = 240/336
Likewise, for the 2nd fraction, since 16 × 21 = 336,
28/16 = 28 × 21/16 × 21 = 588/336
Add the two like fractions:
240/336 + 588/336 = 240 + 588/336 = 828/336
828/336 simplified gives 69/28
So, 15/21 + 28/16 = 69/28
In mixed form: 213/28

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