Subtract 1/16 from 72/21, Solve 3 9/21

Subtract 1/16 from 72/21

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

72/21 - 1/16 is 377/112.

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,
72/21 = 72 × 16/21 × 16 = 1152/336
Likewise, for the 2nd fraction, since 16 × 21 = 336,
1/16 = 1 × 21/16 × 21 = 21/336
Subtract the two like fractions:
1152/336 - 21/336 = 1152 - 21/336 = 1131/336
After reducing the fraction, the answer is 377/112
In mixed form: 341/112

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