Add 72/16 and 9/21, Solve 4 8/16 + 9/21 as a fraction

Add 72/16 and 9/21

1^st number: 4 8/16, 2^nd number: 9/21

72/16 + 9/21 is 69/14.

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,
72/16 = 72 × 21/16 × 21 = 1512/336
Likewise, for the 2nd fraction, since 21 × 16 = 336,
9/21 = 9 × 16/21 × 16 = 144/336
Add the two like fractions:
1512/336 + 144/336 = 1512 + 144/336 = 1656/336
1656/336 simplified gives 69/14
So, 72/16 + 9/21 = 69/14
In mixed form: 413/14

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