Add 9/16 and 75/21, Solve 9/16 + 3 12/21 as a fraction

Add 9/16 and 75/21

1^st number: 9/16, 2^nd number: 3 12/21

9/16 + 75/21 is 463/112.

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,
9/16 = 9 × 21/16 × 21 = 189/336
Likewise, for the 2nd fraction, since 21 × 16 = 336,
75/21 = 75 × 16/21 × 16 = 1200/336
Add the two like fractions:
189/336 + 1200/336 = 189 + 1200/336 = 1389/336
1389/336 simplified gives 463/112
So, 9/16 + 75/21 = 463/112
In mixed form: 415/112

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