Add 21/16 and 16/21, Solve 1 5/16 + 16/21 as a fraction

Add 21/16 and 16/21

1^st number: 1 5/16, 2^nd number: 16/21

21/16 + 16/21 is 697/336.

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

Next, find the equivalent fraction of both fractional numbers with denominator 336
For the 1st fraction, since 16 × 21 = 336,
21/16 = 21 × 21/16 × 21 = 441/336
Likewise, for the 2nd fraction, since 21 × 16 = 336,
16/21 = 16 × 16/21 × 16 = 256/336
Add the two like fractions:
441/336 + 256/336 = 441 + 256/336 = 697/336
So, 21/16 + 16/21 = 697/336
In mixed form: 225/336

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