Add 28/21 and 25/16, Solve 1 7/21 + 1 9/16 as a fraction

Add 28/21 and 25/16

1^st number: 1 7/21, 2^nd number: 1 9/16

28/21 + 25/16 is 139/48.

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,
28/21 = 28 × 16/21 × 16 = 448/336
Likewise, for the 2nd fraction, since 16 × 21 = 336,
25/16 = 25 × 21/16 × 21 = 525/336
Add the two like fractions:
448/336 + 525/336 = 448 + 525/336 = 973/336
973/336 simplified gives 139/48
So, 28/21 + 25/16 = 139/48
In mixed form: 243/48

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